Product: Credit card

I purchased 4 appliances through Best Buy of  XXXX, NY and they offered me to open up a Citi Best Buy credit card account for a 0 % APR monthly installments for my appliances. They did not inform me the expiration date of the promotional period, however once I purchased the items after several days I called up the bank to see where my Best Buy credit card was so that I can login to my account and view the expiration date of the promotional period end date. They mentioned I must wait until I receive the credit card until I can set up the online banking and set up auto-pay etc. Once I received my card I set up my account, however thereafter I was always having difficulty logging into my account and viewing my statements. In XXXX  my grandmother passed away and my grandfather also severely fell ill, therefore I had to make quick arrangements and book flights to travel to XXXX. While I was in XXXX, once again I was not having any access in my Citibank account, it was asking me for an XXXX in order to login. I could not receive an XXXX while I was in another country as my US number was not active, and there was no other way to receive the XXXX other than by phone. I was informed through a bank employee in the past that once my promotional period expires that the entire balance would be paid off from my bank account and routing number on file as I conveyed to them that I do not want to pay any interest, I simply wanted to take advantage of the introductory promo period for opening up a new Best Buy Citi card. While I was in XXXX, I received a few emails regarding a 'minimum payment ' that was being deducted from my account, however I was very confused as I was under the assumption that my entire balance was already paid off in XXXXXXXX XXXX XXXX. Upon my return this week from my trip from XXXX after several attempts I was able to get into my account after resetting the password and when I saw my past statements leading XXXXXXXX XXXX, I have incurred interest of about {$1700.00} which is a ridiculous and insane amount, I was in utter shock and called up the bank immediately. I spoke to supervisors, the hardship department and many individuals at the bank only to inform me that the interest can not be reversed. The balance on my account in XX/XX/year> was about {$3500.00}, and now it has gone up to about {$5500.00} with the minimum payments being paid. I requested the bank to back track and allow me to pay the $ XXXX and waive the interest for the past few months which has amounted to {$2000.00} as they are charging an APR rate of 30 %. This is causing me significant hardship and will be making it very difficult to pay any of my normal expenses. I regret to open a Best Buy credit card account as it has caused me harm, stress and significant hardship to me and my family. I am already going through a difficult time and the bank has deceived me into paying more money. I feel as though I have been scammed, and tricked by Best Buy and Citibank into paying more money than I should have for the appliances. I can not afford to pay this amount in interest. I humbly request you to resolve my issue with Citibank so that they accept my original pay off amount to bring the balance to {$0.00} without any interest, or they can extend the promotional period until this month and I can pay off all of the remaining balance without interest. I graduated from college 2 years ago, and am still paying off my student loans and also paying for my sister 's expenses while my parents are in XXXX. This will cause serious financial distress to me and my sister if this matter is not resolved.