Refund not Processed as Promised

i have sold my vehicle in December 2022 , i have subsequently cancelled my month to month contract and was advised that there is no further cost to me, on 20 December , a premium has been collected , i called in and advised that there was a premium collected , they have advised that it will be refunded , we are now in March and no funds have been refunded , i was waiting for my refund before i add the new vehicle , i will therefore not put in another Tracker product in my car and will rather go to another provider