Increase of interest rates

At end of February 2020 I went off on Absa disability pension. so I am still a staff member. On 1st April I became aware of the fact that the Bank changed my interest rates on my vehicle finance as well as my home loan and with no notice at all. The Consultant at the Bank told me the change was done by the system from head office I logged a complaint at action line on 1 st April with reference C***3. I called in 2 times and was promised feedback within 2 days. Up to now no response and my interest rates were not corrected. After 32 years of service I am really shocked about the poor client service I have received. I would really like a response from the Bank.