which hopping type are you using?
If it’s NH RH with 1×1 or 1×3 pattern you may be facing overshooting cells in your network. if not it’s likely to be:
– a bad functionning of TRU: can be troubleshooted if the bad ICM is the same on all the sectors of the same site
– internal/external interferences (optimize your frequency if internal or deal with the regulatory board for external cases).
also check if the threshold set on the parameter ICM interfband1..5 is not to low