Fatal error: Uncaught Error: Call to a member function fetch_array() on bool

The value of $admin_mail is not an array (or array of results). It is returning false probably which is a boolean value.

Your query 'Select * from proxydb' is returning false. Please check if you really have records in the database for the table proxydb OR the the table name is really without wp_ or other prefix defined at the time of table definition?

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