One of the solution is hard reset.
Just remove the DRUs of particular cell one by one and check after that.
Reason:- Because the DRUs are running by software and possible that the software may be hang.
when u remove & re-insert the DRU it will automatically “HARD RESET”. bcoz there is a small pin behind the DRU. So when u re-insert it will automatically hard re-set and start loading software from BSC.
When u reset from front i.e “SOFT RESET”. The dru will b reset but not the Rx power it is radiating.
So don’t worry. Just remove & re-insert the DRUs.