please clarify

i had a cell c contract for several years. this time when it expired i did not renew the contract. however, i was still using my number. last week i lost my phone. i deceided to get a new phone , i called cell c to order my phone over the phone. the lady who assited me told me that i cannot apply for a new phone becasue my number is permanetly deleted. i last used my phone last week with the same number. what amazes me is that few weeks back i have been receiving calls from cell c ofering me contracts, but now that i need the phone i am told that i cannot have it becasue my number is deleted. and how is the application of the phone has to do with the number , i dont know. can someone help me just to explain to me what they meant that my cell number has been deleted and i cant have a phone. i asked the lady who was assisting me , she said she does not know what it means. note that i never missed my payment when i still had a contract.