Hello @Roman14,
Welcome to the community!
You would need to contact customer service directly and they will assist in cancelling the account, see here for all the different methods to contact them even from outside the country.
You should also note when cancelling a post-paid account and if there is a credit when your final invoice is produced Fido will mail the refund by cheque to the last address on file. However, if you usually pay your bill with a credit card you can request the refund be put back onto the card you will need to make that request before the cheque is issued so you can make the request at the time of cancellation.
