Solution:1
At the end, the easiest way to solved this issue was creating a clean wordpress installation. However, I’m doubtful if this can happen another time at some point. Highly recommend to do backups of the whole site frequently (database, wordpress export, wp-content or the whole “public-html’ where the files are)
Solution:2
Today, I solved my site after check the err log. Many errors were log here with s.t like this: Duplicate entry ‘0’ for key ‘PRIMARY’… => the database have some miss AUTO_INCREMENT field in some tables. So you can check their table name from error log and add AUTO_INCREMENT into the PRIMARY fields. Everything will be OK.