Bests & Worsts Reviews from Amazon

I got this card to save 5% on purchases. When the bill arrived for my purchase I paid in full right away. The following month I received a bill stating that I had not paid. The statement also said I owed a $25.00 late fee and $11.13 in interest. I cannot access my account to check my account. I have tried the online method several times and it will not work. This has been a huge hassle and I will no longer be using this card.I feel cheated and deceived !