If the event is cancelled
If an organiser cancels an event, you'll get a full refund of the ticket price and convenience fee automatically. You don't need to do anything.
If you can't make it
Tickets are non-refundable once booked, unless the event page offers cancellation. Where it does, the window and any deductions are shown on the event page and in your confirmation email.
Failed or duplicate payments
If money left your account but no booking was confirmed, it is reversed automatically within 7 working days. If it hasn't arrived, write to hello@bidmytix.com with the time of payment and the last 4 digits of the card or account used.