Data error in AdSense Error establishing a database connection

Thanks for reaching out. The error you’re encountering refers to a database error, which is independent to your Site Kit setup. From internal tests we’ve encountered this regularly with particular hosting setups.

So we can determine more on this in your case please share the following information:

1. Your Site Health information. You can use this form to share privately if preferred.
2. Can you share your Site Health status (Tools > Site Health > Status), which differs from your Site Health information. I ask as there are usually database errors output in this report.
3. Have you tried to disconnect the AdSense module before connecting once more? (Site Kit > Settings > AdSense > Edit > Disconnect AdSense from Site Kit)

We’re also working on a solution for the HTML markup in this error your encounter, which shouldn’t be output along with the error details. You’ll find out more on this below:
https://github.com/google/site-kit-wp/issues/4169

As we haven’t received a response, I’ll mark this as resolved. Feel free to open a new support topic if you continue to encounter issues, or reopen this topic and we’d be happy to assist. Thank you!

Actually, it was not resolved. But I saw similar problems reporting by different people and the same guy from word press responding in the same way. It was concluded without any result. I thought I could fall in the same loop without any result, in the end (it will be just a waste of some time), I shall not be able to fix it (at least it is not harming me seriously). It is OK that you have closed it.