Bad Service CellC

I Aphele Mooi have a contract phone with Cell C for a (Honor 50 Lite, number ***) and have been paying on monthly basis + insurance, but in October i lost my phone and when tried to submit a claim, all of a sudden i was told that my contract was cancelled, but i was using the phone when i lost it and according to my knowledge i was upto date with my payments (proof of payments provided), it's now over a month trying to get this sorted out and I'm still being given the run around and still without a phone/solution after I've been paying for the phone, i have submitted proof of payments multiple times for this to get sorted, but still nothing!