Help! Door opens from outside when locked!
 

I know I already posted in the S70 category but was hoping someone outside that may have an idea. I was changing my speakers and as i put the door on I was double checking all my buttons. The lock pin didn't seem like it was going up all the way when I was hitting the unlock button, I pulled on the inside door handle and hear a pop. Now when the car is locked that door can still be opened just like if it was unlocked. I've taken the door off and checked everything I can find but am still baffled. Help please?