The first thing you should do is try to minimise the damage. Turn off the stop tap if it’s a leak. Call people who are in a position to help – the emergency services, the landlord, your parents; the Hiro home emergency service if you have it!
When everything’s safe, make a cuppa and tell us everything that’s happened. Use the Hiro app, or call us on 0203 991 3330 (0203 991 3330 from overseas). If you can’t do either of those things you can even use the chat function on this website.