Contract phone replacement

I upgraded my contract with Mtn in April & received my delivery on the 26th of April. Took the phone back for warranty assessment on the 11th of May 2023 in store. Followed up with the store 24th June, told assessment was approved I must get a new phone but because I took it online the store can’t give me. I was given the RMS to provide as proof of approval that I due for a new phone. Given no *** I’ve calling the whole day, transferred to sales from sales to ccs depart to Mtn direct depart but no one can assist me and yet I’m paying for the phone I don’t have. This is now frustrating because the store can’t help me & I can’t get someone on the phone to assist me.