3 months waiting no feeback, pillar to post reaponses

I have logged a debit order dispute with fnb end of January or beginning of February 2020, I was advised of the 40 day waiting period. Did follow ups via online several time and I was given a number to call foe debit order which they never answered. I then contacted the online however now given an email that I have escalated to on the 05th May still no feedback. Why is fnb doing this fo their customers. Im thinking of moving to a caring back because i havd been banking with fnb foe more than 10 years. Jow do u close the account and move fo another bank