Terrible credit card department

Overhaull i have been very happy with FNB Banking , but lately the credit card division of FNB is damaging the reputation and trust of the bank . I have emailed them endless amount of times , first one on 9 June regarding a dispute , which they answered within 48 hours with the most stupid and insulting way . After that they just ignoring my emails even after i approached my branch for help . Over the phone is IMPOSSIBLE to get hold of anyone. What must i do with this *********** department of the bank to assist my dispute . CANCEL MY CREDIT CARD PAYMENTS SO THAT THEY PAY ATTENTION ???? I WILL DO ………………….