i request that you payout my phone you have been keeping 3 months without my consent i agreed to 15 days

i herewith reguest that cell c payout my phone . i had to get another phone as they can not tell me where my phone is or whats happening numerous times i have asked they do not know in jan it would be 3 months , i request full payment of my phone . i no longer need the phone that you can not tell me whats happening with it or any feedback from cell c at all exept looking into it