Citi - Shell Gas MasterCard Review

I had a Citi Shell Gas Mastercard util I got a $39 late charge on my $50 balance.  Here's what happened.  I pay most of my bills online and I have my account set up to receive statements via email rather than regular mail.  When I went to pay my bill on the Citi website, it told me I was unable to make my payment and to try again later.  I tried a couple more attempts but it was still down so I ended up getting a $39 late fee.  I thought it wouldn't be a big deal.  I'll just call and tell them what happened.  When I called, they didn't care what my reason was. They were not going to take the charge off.  They said I should have called the payment in or sent a check.  I thought it was ridiculous to charge someone $39 for a late fee on a $50 balance.  Also, my credit score is very good and I never get late charges.  Needless to say, I canceled the card.  I will never use another Citi card as long as I live.   No wonder they are in financial trouble, they don't care about their customers.  They only want to rip them off.