I recently downgraded both my checque and credit card with FNB

I recently downgraded both my checque and credit card with FNB. My credit card had a set limit split, them suddenly on the new account I see they changed the limit split with my consent and my card is now overdrawn due to that as the set the straight limit to a lower amount than I initialy had then increased the budget limit .Debit order for this month is my entire salary because of this. I have been trying to call their call center and I am forced speak to a robot or use a chat. This evening I tried the chat Ntombifuthi tells me my account is with collections.? How when I have not missed single payment? And she can't help me further. What **** service is THIS? so much for prouding yourselves with the so called how can we help you when you are of no help! I simply asked for a downgrade not this MESS!!!!!!