How to ***** clients over just to make a buck

I have been a client of Edgars for 22/23 years and for the past 8-10years i have been paying R2500 p/m. Last week Friday i received an SMS informing me that my payment terms have been changed from 6 months interest free and they apologise for the inconvenience. This is definitely NOT what i signed up for when this account was opened 1997/98. Not even the decency to call me and explain all this then give me a chance to decide if i want to keep the account or not then make arrangements to pay off what i owe them, nothing civil like that.

now i am forced to pay more than i wanted not by choice but FORCE. all my accounts are 6 months interest free except for Mr P but i got into that contract knowing fully well the conditions and terms or the contract. not this nonsense Edgars is doing.