Awful! The money for the tickets came out of my account twice. When I tried to resolve this with customer service I was told I might be given a refund on the second payment if they decided something was wrong. The customer service advisor would not let me speak and kept telling me conflicting information. He promised me a manager would speak to me in 24 hours, then said they would call me back later than this. I was asked for too much personal information (contravening GDPR) and basically called a liar. He also told me that these double payments happen all the time, but they don't happen!! Don't use the Trainline!!