FBN changes balanced without any communication - balances I just being changed on the fly

FNB increased my credit total limit and after 5 days the card reflected lower credit total limit than what was specified on the agreement latter without any communication, is this ***** or something????? I mean without any communication balances I just being changed on the fly just within a few days.

Pathetic service from FNB bank - Capitec is way much better that FNB, my I should consider moving there and leave all this ****.