Thank you Pavel.
These are the versions I use:
PHP - 7.2.13
ATUM - 1.5.3.3
WP - 5.0.3
WC - 3.5.4
It does show in the Woocommerce - Status - Active plugins tabel that ATUM = "Not tested with the active version of WooCommerce"
Could there be some sort of issue?
Sorry, couldn't upload it separately, so added it to this post, the LOG Fatal errors.
2019-02-05T20:08:04+00:00 CRITICAL Uncaught WC_Data_Exception: Invalid or duplicated Supplier SKU. in /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/woocommerce/includes/abstracts/abstract-wc-data.php:785
Stack trace:
#0 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/atum-stock-manager-for-woocommerce/classes/Models/Products/AtumProductTrait.php(237): WC_Data->error('product_invalid...', 'Invalid or dupl...', 400, Array)
#1 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/atum-stock-manager-for-woocommerce/classes/Inc/Helpers.php(1698): Atum\Models\Products\AtumProductSimple->set_supplier_sku('S001')
#2 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/atum-stock-manager-for-woocommerce/classes/Inc/Ajax.php(452): Atum\Inc\Helpers::update_product_data(20388, Array)
#3 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-includes/class-wp-hook.php(286): Atum\Inc\Ajax->update_list_data('')
#4 /home/milspvc154/domains/mil in /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/woocommerce/includes/abstracts/abstract-wc-data.php on line 785
2019-02-05T20:08:24+00:00 CRITICAL Uncaught WC_Data_Exception: Invalid or duplicated Supplier SKU. in /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/woocommerce/includes/abstracts/abstract-wc-data.php:785
Stack trace:
#0 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/atum-stock-manager-for-woocommerce/classes/Models/Products/AtumProductTrait.php(237): WC_Data->error('product_invalid...', 'Invalid or dupl...', 400, Array)
#1 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/atum-stock-manager-for-woocommerce/classes/Inc/Helpers.php(1698): Atum\Models\Products\AtumProductSimple->set_supplier_sku('S001')
#2 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/atum-stock-manager-for-woocommerce/classes/Inc/Ajax.php(452): Atum\Inc\Helpers::update_product_data(20388, Array)
#3 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-includes/class-wp-hook.php(286): Atum\Inc\Ajax->update_list_data('')
#4 /home/milspvc154/domains/mil in /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/woocommerce/includes/abstracts/abstract-wc-data.php on line 785
2019-02-05T20:08:30+00:00 CRITICAL Uncaught WC_Data_Exception: Invalid or duplicated Supplier SKU. in /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/woocommerce/includes/abstracts/abstract-wc-data.php:785
Stack trace:
#0 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/atum-stock-manager-for-woocommerce/classes/Models/Products/AtumProductTrait.php(237): WC_Data->error('product_invalid...', 'Invalid or dupl...', 400, Array)
#1 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/atum-stock-manager-for-woocommerce/classes/Inc/Helpers.php(1698): Atum\Models\Products\AtumProductSimple->set_supplier_sku('S001')
#2 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/atum-stock-manager-for-woocommerce/classes/Inc/Ajax.php(452): Atum\Inc\Helpers::update_product_data(20388, Array)
#3 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-includes/class-wp-hook.php(286): Atum\Inc\Ajax->update_list_data('')
#4 /home/milspvc154/domains/mil in /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/woocommerce/includes/abstracts/abstract-wc-data.php on line 785
2019-02-05T20:08:48+00:00 CRITICAL Uncaught WC_Data_Exception: Invalid or duplicated Supplier SKU. in /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/woocommerce/includes/abstracts/abstract-wc-data.php:785
Stack trace:
#0 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/atum-stock-manager-for-woocommerce/classes/Models/Products/AtumProductTrait.php(237): WC_Data->error('product_invalid...', 'Invalid or dupl...', 400, Array)
#1 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/atum-stock-manager-for-woocommerce/classes/Inc/Helpers.php(1698): Atum\Models\Products\AtumProductSimple->set_supplier_sku('S001')
#2 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/atum-stock-manager-for-woocommerce/classes/Inc/Ajax.php(452): Atum\Inc\Helpers::update_product_data(631, Array)
#3 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-includes/class-wp-hook.php(286): Atum\Inc\Ajax->update_list_data('')
#4 /home/milspvc154/domains/milsp in /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/woocommerce/includes/abstracts/abstract-wc-data.php on line 785
2019-02-05T20:09:59+00:00 CRITICAL Uncaught WC_Data_Exception: Invalid or duplicated Supplier SKU. in /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/woocommerce/includes/abstracts/abstract-wc-data.php:785
Stack trace:
#0 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/atum-stock-manager-for-woocommerce/classes/Models/Products/AtumProductTrait.php(237): WC_Data->error('product_invalid...', 'Invalid or dupl...', 400, Array)
#1 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/atum-stock-manager-for-woocommerce/classes/Inc/Helpers.php(1698): Atum\Models\Products\AtumProductSimple->set_supplier_sku('S001')
#2 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/atum-stock-manager-for-woocommerce/classes/Inc/Ajax.php(452): Atum\Inc\Helpers::update_product_data(631, Array)
#3 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-includes/class-wp-hook.php(286): Atum\Inc\Ajax->update_list_data('')
#4 /home/milspvc154/domains/milsp in /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/woocommerce/includes/abstracts/abstract-wc-data.php on line 785
2019-02-05T20:20:50+00:00 CRITICAL Uncaught WC_Data_Exception: Invalid or duplicated Supplier SKU. in /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/woocommerce/includes/abstracts/abstract-wc-data.php:785
Stack trace:
#0 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/atum-stock-manager-for-woocommerce/classes/Models/Products/AtumProductTrait.php(237): WC_Data->error('product_invalid...', 'Invalid or dupl...', 400, Array)
#1 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/atum-stock-manager-for-woocommerce/classes/Inc/Helpers.php(1698): Atum\Models\Products\AtumProductSimple->set_supplier_sku('S001')
#2 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/atum-stock-manager-for-woocommerce/classes/Inc/Ajax.php(452): Atum\Inc\Helpers::update_product_data(631, Array)
#3 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-includes/class-wp-hook.php(286): Atum\Inc\Ajax->update_list_data('')
#4 /home/milspvc154/domains/milsp in /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/woocommerce/includes/abstracts/abstract-wc-data.php on line 785
2019-02-05T20:21:40+00:00 CRITICAL Uncaught WC_Data_Exception: Invalid or duplicated Supplier SKU. in /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/woocommerce/includes/abstracts/abstract-wc-data.php:785
Stack trace:
#0 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/atum-stock-manager-for-woocommerce/classes/Models/Products/AtumProductTrait.php(237): WC_Data->error('product_invalid...', 'Invalid or dupl...', 400, Array)
#1 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/atum-stock-manager-for-woocommerce/classes/Inc/Helpers.php(1698): Atum\Models\Products\AtumProductSimple->set_supplier_sku('S001')
#2 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/atum-stock-manager-for-woocommerce/classes/Inc/Ajax.php(452): Atum\Inc\Helpers::update_product_data(631, Array)
#3 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-includes/class-wp-hook.php(286): Atum\Inc\Ajax->update_list_data('')
#4 /home/milspvc154/domains/milsp in /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/woocommerce/includes/abstracts/abstract-wc-data.php on line 785
2019-02-05T20:21:50+00:00 CRITICAL Uncaught WC_Data_Exception: Invalid or duplicated Supplier SKU. in /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/woocommerce/includes/abstracts/abstract-wc-data.php:785
Stack trace:
#0 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/atum-stock-manager-for-woocommerce/classes/Models/Products/AtumProductTrait.php(237): WC_Data->error('product_invalid...', 'Invalid or dupl...', 400, Array)
#1 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/atum-stock-manager-for-woocommerce/classes/Inc/Helpers.php(1698): Atum\Models\Products\AtumProductSimple->set_supplier_sku('S001')
#2 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/atum-stock-manager-for-woocommerce/classes/Inc/Ajax.php(452): Atum\Inc\Helpers::update_product_data(631, Array)
#3 /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-includes/class-wp-hook.php(286): Atum\Inc\Ajax->update_list_data('')
#4 /home/milspvc154/domains/milsp in /home/milspvc154/domains/milspecvehicles.co.uk/public_html/wp-content/plugins/woocommerce/includes/abstracts/abstract-wc-data.php on line 785