Product: Credit card or prepaid card

On XX/XX/XXXX I received notification from XXXX XXXX that my Best Buy Citbank card was over my credit limit. Ultimately, impacting my credit score. That day, I immediately called Citibank to ask what was going on. The customer service representative had informed me that a XX/XX/XXXX Best Buy promotion had just ended and I was retroactively charged interest. I apologized and told the customer service representative that I had no idea and would like to make a payment to pay off the balance right away. She informed me she would be able to waive the interest for that XX/XX/XXXX promotion as a courtesy for a long-time, on-time paying client - however, XX/XX/XXXX, I had already made a payment for {$500.00} and the amount I needed to pay was {$600.00}. I was unable to put through the {$100.00} that same day so she told me she would annotate the account and I could make the payment tomorrow then call again to have the interest waived ( {$270.00} ). 

After I hung up the phone, I was able to do a little more investigation and review my statements because I was not sure how my Best Buy promotions got so out of hand when I was making {$100.00} payments which were over the amounts that I had owed and should have paid the 0 % APR for 12-18 months at least a couple months ahead of time to then be applied to the next promotion so I wouldn't be behind. I called again XX/XX/XXXX to discuss what was going on with the account. 

I was informed that back in XX/XX/XXXX, a promotion had ended where {$23.00} had not be paid off. I had incurred retroactive {$430.00} interest on the card. I was informed that when the {$100.00} payments had been going through, they are applied to interest first, thus throwing off the timely manner in which the promotions should've been paid by 5 months. 

The next promotion ended on XX/XX/XXXX, where I was retroactively charged {$1000.00} and a XX/XX/XXXX promotion ended where {$160.00} in interest was retroactively charged, totaling {$1200.00} for the month of XX/XX/XXXX. 

On XX/XX/XXXX, thinking that my account was in good standing and there were no late payments. I made a purchase at BestBuy of {$200.00}. My balance per my XX/XX/XXXX statement said that it was {$4700.00}, while my credit limit is only {$4800.00}. This charge put me over my credit limit since I had not known about the promotion that recently ended and the retroactive interest that had been charged in XXXX. 

My question is, why was my card not declined on XX/XX/XXXX? I would have been able to call when I was declined to figure out what was going on with the account and asked why my card had been maxed. My payments have never been late. When asking management why this occurred, she could only tell me that " some accounts are allowed to go over the limit ''. I don't recall ever enabling over-limit protection for this card. Most credit cards do not allow for over-limit protection because it can ultimately hurt the consumers credit. It should be Citibank/Bestbuy 's responsibility to turn off the card and provide a hard stop or decline when the max has been reached as an indicator that the consumer needs to give the bank a call. Particularly, since interest for the best buy cards are retroactively charged and a consumer may not be aware that a promotion had ended. 

My problem is, that had I got the decline on XX/XX/XXXX and called Citibank, they would have waived the XXXX interest if I agreed to pay the XXXX promotions in full ( which I was happy to do and I was informed this by management ). This falls within their 60 day rule for a 1 time per rolling 12 months to waive interest on behalf of the customer. Had Citibank informed me and given me a hard-stop when I tried to make the purchase, I would've been within the allotted period, I could've remedied the situation and the XX/XX/XXXX promotion would've been able to been paid off right away as well since that was coming up shortly there after. 

I was only able to have XX/XX/XXXX 's interest waived because unfortunately, I had called too late given I only received a notification from XXXX XXXX that my credit score had drastically dropped with a maxed card. All because this wasn't within the 60 day period. I have been a loyal customer since XXXX. I've never had a late payment and they clearly feel good enough about my timely payments to enable me to make over the limit purchases by {$180.00}. 

I had spoke with about 4 managers/supervisors who all told me that because I had already been granted the XX/XX/XXXX interest waive that I would not be able to remedy the XXXX interest retroactively charged so I am now paying about {$1300.00} in interest, along with interest that has been accruing since, on top of the remaining balances that weren't paid timely. I had even asked if they would consider retroactively charging the interest for XX/XX/XXXX and I would pay it if they could waive XXXX instead since that is the largest one. Keep in mind, I have never called to waive any other interest in my entire history of the account. This is my first time I am running into this issue. 

I believe Citibank is taking advantage of me and alike customers with retroactively charging interest when promotion periods end and not giving them a proper notifications such as a credit card decline ( an act of protecting consumer credit ) in order to reap the benefits of retroactive interest being paid. I did not receive any communication from Citibank regarding this and I would hope they would make right of the situation by granting an exception given that they have failed due diligence to the consumer by declining payment. This will never happen again on my behalf and I have paid the promotions to date, excluding interest for now.