Customised plugin failed to install and activate

Unsure of what I did but it seems to be working now. It may have something to do with the fact that I renamed the main php file to try and avoid a conflict. If I keep it the same file name it “registers”.

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