clutch pedal stuck on the floor

I have a 05 vw jetta gli 1.8t 6spd. I was driving and the clutch pedal stuck to the floor. I found that the hydraulic line came out  before the bleeder. the line wasnt broken and the clip and oil seal were still intact. I resecured the line and bled the system. I drove another 20 miles(city driving) and the line came out again. Has anyone else had this problem before? The line,clip,and oil oring are all in good shape with no signs of wear. If anyone can help I would appreciate it. Thanks.