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In such cases the Guard Certificate (GC) issued by the train superintendent, TTE, Guard etc must be obtained and sent along with ticket in original to the following address immediately:
Indian Railway Catering & Tourism Corporation Ltd.,
2nd Floor, STC Building,
1, Tolstoy Marg,
New Delhi -110001
IRCTC will process the case with the Refunds office of the concerned Railway where the train had originated & request for the refunds as due. After verification of the records from the concerned railway, the refunds office sanctions a refund which is sent to IRCTC. IRCTC on receipt of the same credits it to your credit card / bank account. This process may take anything from 3 - 6 months or more depending on the processing speeds, record verification etc. at the concerned Railway Stations.