Was shooting tonight, reached the 2K round mark. Well in the midst of firing, I fired and the trigger would not return forward. The slide was not locked up, a fresh round was chambered. To get the firing pin to fall I had to turn the pistol upside down smack down against the mag well and push the trigger forward then pull it bag as usual. Any ideas on what the prob is? I am sending to springfield tomorrow after I clean it. Any insight will be greatly appreciated.