You can edit the price of a paid post even after it’s been published or purchased. To do this:
Go to the post you want to update.
Click on the three dots in the top right corner.
Select "Edit" from the dropdown menu.
You’ll be taken to the Post Builder. Go to the Settings block and find the Post Cost section.
Adjust the price to your preferred amount.
Click "Save" to apply the changes.
This allows you to change your pricing if needed, whether for a promotion or to update your offer.