My garage door has the same problem. I phoned Barcol and the guy told me it is a easy fix. Usually because the two sensors above the ground are not in alignment. 2 T+ }! t. N1 k! d4 Z+ Q! R/ o 0 k+ {, R" _0 Z* zThe sensors are located on each side of the garage door. You can manually adjust to make them align. 2 ^2 ?/ ^6 H8 u $ Q* {/ ^7 _$ eMy husband did exactly the same thing and fixed the issue. 7 ^+ v0 I W8 N + G4 ]9 E+ x/ |+ uHope this will help you bit. Sorry. I can't type in Chinese now.