A family member of mine has received an email saying they've been identified as having reused a ticket. The ticket reference has been provided and we've worked out they used this ticket 3 times in total (i.e 2x more than they should). The ticket was bought on Trainline so would have been scanned by inspectors multiple times. There has been no mention of prosecution but they've asked for a response within 7 days. At this point is the right course of action to say "yes I must have reused the ticket" and offer to pay for the extra travel costs + any fine they issue?