My rear windscreen washer on my mk1.5 focus has stopped working

Last weekend it was working until i noticed more water was dripping inside than out..
So took off the 3rd brakelight and noticed the the wee pipe had popped off, so simply put it back on and it worked perfectly again..
Then on monday, it wasnt doing anything, no water was coming out the pipe on its own
Any ideas whats up with it and/or how to sort it?
Cheers