Refunds are not directly available from MainGate Tickets. Refunds are solely at the discretion of the promoter. Thus, you should contact them for a refund request.
Exchanges (Ticket Swaps) are permitted by certain promoters in order to allow users to change the date they attend their event. For instance, if a user purchases tickets for an event happening Saturday but then decides Sunday would be better, the user can email the promoter and request a Ticket Swap for Sunday. If it is possible, the promoter will make the current set of tickets valid on the newly chosen day. New tickets will not be sent out. Some non-participating venues (and artists, teams, etc.) have a "no refunds or exchanges" policy.
If an event is canceled, The users ticket price plus taxes and facility fees will be refunded. The user will be contacted if such an event should occur.
If an event is rescheduled, The promoter or Maingate will contact the user with the new date and time ASAP. Refunds are at the discretion of the promoter or venue.