If I sent you a link is because it's explained there and you have not confirmed that you are using the "Set Purchase Price" modal to set the purchase price. In your last message, you sent me a screenshot that has nothing to do with the "Set purchase price" modal.
And you are still not confirming that. I need to know if you are doing it right to move forward. I hope you understand this...
Please, confirm. Are you clicking on this link:
And setting the price with the modal that opens afterward.
If you are doing so and the price is not updating, please open a private ticket and give us access so we can investigate it.