Error establishing a database connection for all my sites

Support
1

For both sites I run (one of them is very important) suddenly the database connection is not happening and I get the error: Error establishing a database connection. I’ve tried a few things I saw on this forum, but so far no luck. Do you have any idea what could be going on? I’ve attached the error log.

error.log (3.1 MB)

2

I still don’t know what caused it, but luckily I was able to restore my sites by reimporting them with this info: https://getflywheel.com/wordpress-support/how-to-import-a-wordpress-site-into-local/