Upgrade done - No device in possession - Being Billed for 2 phones.

I have upgraded my contract on the 25/02/2022. i have requested an A12 128Gig phone. the wrong phone was sent. I returned the phone on 01/03/2022 received a Ref IRMS761321. Ever since the 01/03/2022 i am calling MTN Direct to cancel the contract and do a new contract and no one can help. I get help from a consultant for a new Upgrade for an A31 but still no phone. Called a supervisor by the name Slindiwa who promised to sort the issue but still nothing. I received a bill today with the amount of R2 493.17 And i am being billed for 2 different phones and no one in MTN can help. Its almost 1 month now i,m trying to get help from MTN and every time its being an excuse. This is so disappointing. When they need to upgrade you its done in 10 mins but when they do the wrong we customers are suffering. I have been an MTN customer for years and this is how we are treated. All i need is my contract to be sorted out and my bill corrected ASAP as i have waited too long now. You are welcome to get all my call recordings.