I’m sorry, it appears you have tried to pay with a link to a DONATION price from before the pricing changes effective April 1, 2025.
To pay, rather than using that link, you need to first make sure you have at least release 6.30 of DONATION. You can use Tools -> Check for Updates to update, if necessary.
Then you can use the new Tools -> Subscription Management Portal menu option to pay the appropriate price, which is now based on the number of donors you have in the current year.
Thank you.