Product: Credit card

In brief, I unknowingly missed the promotional end date for the promotion I was under and as a result, my {$2500.00} account received a {$1300.00} deferred interest charge. 

In XX/XX/XXXX, I was accepted into a school program that required me to purchase an XXXX computer. We did not have the funds for a cash purchase, so we applied for a barclay credit card. The Barclay card that we were offered included a XXXX deferred interest promotion on the purchase. After buying the computer, I set up the paperless statements and Autopay, so that I would n't miss any payments with my busy school schedule. 

We planned to pay off any remaining balance on the card before the promotional period, however, I have not received any notification from Barclay regarding the ending promotional period. I thought the end date should be coming soon ( around XX/XX/XXXX ) so I logged onto the account on XXXX XXXX to go ahead and take care of everything and pay off the credit card. To my surprise, I found that I was XXXX weeks late and the promotional period had ended on XXXX XXXX and I had been charged {$1300.00} in interest on a {$2500.00} principle balance. This interest charge was totally unexpected. I neither expected to see that the promotional period had ended, nor had I expected such an astronomical interest charge. I called and talked to multiple managers and team managers at Barclay, and I learned what had happened. 

I received paperless statements, and signed up for autopay, both of which I felt were the most responsible way to handle this new credit card, but this worked against me. The email notifications that come with the paperless statements do not give any indication of the approaching end date of the promotional period and no communication was received by myself, from barclay, to inform me that the promotional period would end or that I would have a {$1300.00} interest charge to my account. I also found out that I would need to login to the account to view the statement and see this deferred interest information, however, that was not made apparent to me in any way and I was under the impression that the autopay and email notifications had negated the need for frequent account logins and statement checks. This lack of notification has caused me to be a mere XXXX weeks late and to incur a substantial interest fee. While trying to resolve this on the phone with Barclay, I offered to pay the principle balance immediately if we could waive this interest fee, but I have not been able to achieve this. They were only willing to waive {$500.00} of the interest, which is helpful, but still leaves me with an {$820.00} interest charge. I feel like, because of the lack of communication, this interest charge snuck in on me, whilst i was attempting to do the responsible thing. 

I also feel like I was deceived with the meaning of " deferred interest. '' This was XXXX of my first credit cards, and feel taken advantage of, because I had no idea that this is what deferred interest results in. I thought it was an analogy to 0 % interest, and different companies use different terminology. 

I am a student in XXXX school, and my only sources of income are student loans, as my program does not allow employment. If I can not get this resolved my only option is to pay this interest fee with another loan, maximizing my loss in this situation.