Hi. Check TSs on Abis side…For example, one your cell has 6 (3 static and 3 dynamic) timeslots, but if it has less number of them on Abis, for example, 4 timeslot for this cell, then most probably 2 of 6 your timeslots are not using…That’s cell can has congestion.
If it is so, then increase number of timeslots on Abis it can help…