********** interantional transaction

Had ********** transactions that went off my account, logged a dispute and was refunded the return debit fees, however the ********** amount that was debited from my account has still not been refunded...requested feedback from the complaint consultant and have not received a response, ref: RE: ***.

I would like to now, how is it possible for an inernational transaction be declined due to insuffiecient funds but still be allowed to go off my account...i dont have an overdraft facility, why was this transaction processed by the ban...