WP Links from Facebook and Google Ads shows invalid characters

Your problem might be caused by WP Rocket. Turn it off to confirm it, and then you could try out this:
https://docs.wp-rocket.me/article/64-fix-utf-8-issue-with-special-characters

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)