I bought a month to ...

I bought a month to month uncapped WiFi router from MTN on the 30th of May and it was supposed to be delivered on the 03 June I never received it till today I went to MTN Meadowdale for assistance and I was assisted by Linda who promised that MTN will refund me within second week of June I waited and the refund never happened I tried calling MTN several times with no success...now they are sending me the emails and messages that I did not pay the monthly installment all I need is a router or a refund please help 🙏 I