Declined home loan application

I had contract account with mtn a month before expiry i called requested it to be cancelled. I was told to call few days before the actual expiry date which I did. But because they were on strike the contract was never cancelled. Then I got billed for services I never used. This query dragged for long as I was getting debited until I thought it was resolved. Today I got a letter from the bank that my home loan application declined only to find out that it due to the MTN account