Hello,
It seems that you are currently using the Rank Math PRO plugin, but the account you have used to open this ticket is a Free account.
Can you please search and forward a receipt from FastSpring.com so we can locate your account and verify it?
Can you please confirm if you can see the correct number of credits here: http://rankmath.com/my-account/websites.

If you can see the correct number of credits here like in the image above but not on your site, then this is a problem with the syncing of information between rankmath.com and your website. Disconnecting and then reconnecting your account should mostly resolve this
Kindly follow these steps:
1 . Please verify that you’re running the latest versions of the Rank Math plugins: https://rankmath.com/changelog
2 . After that, you may try disconnecting and re-connecting Rank Math to see if that works for you.
You can disconnect your account by navigating to WordPress Dashboard > Rank Math > Dashboard > Help and then simply disconnect the account by clicking on Disconnect Account.

3 . Once you’ve disconnected your Rank Math account, you can connect it again in the same settings. In order to connect your correct account, click on Connect Now.

4 . Once you click on Connect Now, please ensure that you’ve selected the correct account and then click on OK, Activate Now.

5 . After doing this, refresh the credits to start using Content AI. Please head over to WordPress Dashboard > Rank Math > General Settings > Content AI and refresh the credits.
Here’s a screenshot for reference:

Hope this helps, and please do not hesitate to let us know if you need our assistance with anything else.
Thank you.