Daihen OTC Collision Detection

Currently using an OTC FD series robot (i unfortunately do not know exactly what model it is). Last week, the pendant said there was a collision detect. I attempted clear the error and even tried to take it to its home position, but nothing would work. I cant go forward or backwards through the program, but i can move it manually with the XYZ buttons. Just wondering if anyone has had this problem before and if so how did you get past it.