I was fishing this evening and after I caught a good sized bass, I flipped the bail on my spinning reel and made a cast.  For some reason, after that cast the bail lost its firmness and just went limp.  When I tried to reel my lure in, the bail didn't flip, it just kept spinning around and I had to put it down manually.  If you tipped the rod upside down, the bail would flip due to gravity.  It's like it lost all it's resistance.  Has anyone ever had the same issue?  If so, how can I fix it?

Woke up and couldn't get back to sleep. Checked in here and saw your post. 

Probably just snapped the spring, is it an old reel? You may be able to get a replacement bail assembly. Depending on the age/brand and your mechanical ability you may need to take it to a shop.