Track pad left click not working.

So my track pad left click its not working. It will not click anymore and it has sinked. anybody has had the same problem?

do I have to replace it? I got no warranty and I opened it fixed it, worked a few days and its back again to the same. I have PC laptop certifications from Dell latop and desktop but I love my mac and haven't found a solution. just need to know if anyone knows anything else before I purchase a MBP 13" trackpad for 70 bucks.