False Advertising for Upgrades

I did an upgrade for the s20 which was supposed to come with a steriliser case. I did this upgrade online, a MTN Champion called me to verify my upgrade and assured me all was in order and I would get delivery within a week. On delivery I received the phone with no case. I called MTN and was re-directed numerous times but to no avail of any help. I sent an email to MTN Ref no. *** on the 8th Feb 2021, to date no one has contacted me, nor can I get through to any operator at MTN that is willing to help me. I have sent another email Ref. No. ***. Is this their service level we must now accept???