hello,
a drop is not related to utilization vs. capacity, it is probably:
– a radio problem (bad coverage, interference)
– or, a hardware problem (faulty TRX, faulty Abis, faulty BSC board)
– or, a software problem (reset the hardware to fix the problem)
Other possible (rare!) problems include:
– faulty MS
– NSS is waiting too long to reply / or sends an invalid response
…