IuPS port Utilization not balancing on HUAWEI RNC

Hi experts,
I have six(6) IuPS interface ports configured on a Huawei RNC. Some of the port utilization are always high but some are also always as low as 25%. The high ones are in the range of 80% to 94%.

Can you please help me understand this trend as IuPS are in a pool and ideally, the ports should be balanced.

If there is any process in U2020 to resolve this, I will be much grateful to know.