I was offered a no interest balance transfer if paid off within 18 months as long as I made a minimum payment towards that balance transfer each month. I continued to use the card as usual for other regular purchases. Despite the fact that I regularly paid the outstanding balance in FULL and more than the required minimum payment, I was still charged interest on an unknown amount and Wells Fargo was either unwilling or unable to tell me exactly how or why they calculated the interest fees - I called twice to inquire about this issue and was not given satisfactory answers at either time. Finally, I was told that the only way to avoid interest fees was to pay the entire balance in FULL immediately. This feels like a bait and switch since I was never able to gain the benefit of the no interest offer that was made. This has happened for several billing cycles thus far. 
