Incorrect authorization to IMAP from PHP

I'm developing a website where the users can access their mailbox from my application. When I try to connect to IMAP with wrong credentials accidentally, the screen waits for a long time and the server resources are taken up 100% and even if we close the browser we have the same 100%. Who can explain me how thi开发者_开发技巧s happens and how can I catch the case when the username and password are wrong. I'm using this class to connect to IMAP server, but even without it, when I'm using PHP's native imap_open() I have the same issue.

because of attempt time out

I had the same issue