I have a credit card with Barclaycard and my interest charge varies very much from month to month. Been going through quite a few financial struggles and I am unable to pay the full card at once. I am trying to pay it a bit at a time but these interest charges make it a bit impossible. I pay at the same time of the month and the total that I owe is around {$3500.00}. Interest charges are : in XXXX : {$35.00}, in XXXX {$520.00} + {$36.00}, in XXXX {$68.00}, in XXXX {$69.00}. Even though I pay over the minimum, I continue to have {$0.00} in the account because I went over my limit with the fees. I know this is my fault for not being able to cover it but I need to go through a few more months until next year when I believe I will be able to pay it in full. Not sure what is going on with the fees. 
