Never had so much trouble in all my life!!

SO... I had my credit card with Tesco for a couple of months before it all started going wrong. I was using their online banking and soon enough they would block my log in details EVERY TIME I tried to log in. I thought the first couple of times I was in putting them wrong and there probably was times when I was! However, I had these details written down and as soon as it said 'log in failed'once I'd get the details to ensure I was inputting the right digits... still block me out.
Then every time you want to reset your password, you have to phone up and spend 10 minutes on the phone resetting everything and going through security. I stopped using my card for a while.. then I thought I'd give it another go... was fine for about3 months? And now this is the second time in 2 weeks I'm going to have to phone to reset my details.
I saved my computer so it would be a 'trusted' computer to log in from so I could reset my password that way - nope! Didn't recognise it.
I'm fuming.
I've had enough. It shouldn't be so hard!!!

And, if you miss a payment not only do you have to pay interest on the money on your account but also £12! Money grabbers :').
As soon as I get home from work I'm phoning, paying off anything on their and then cancelling!!