I have often used Skype to call phones in the USA from the UK. Suddenly I was unable to do it. I was pretty sure I had credit left (I usually buy in £50 chunks) but it said that my credit was not "activated". I followed the instructions to reactivate it and then bought another £10 of credit. I still cannot make calls - the number sounds like it rings but disconnects immediately. The call log shows "internal error" for each failed call. I've been round in circles trying to reach Skype and find out what's wrong. I followed their instructions to get help but reached a point (several times) where I should have had an option for LIVE CHAT support, but that option did not exist. I give up but they have my money.