My jQuery Ajax form submit is still refreshing page?

You use wrong js event. You register your callback with this code:

$('#form-pm').on('send', function(e) {

But there is no event called send on form. It should be submit. Here’s fixed version of that line:

$('#form-pm').on('submit', function(e) {

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