Dissatisfied with MTNSA Service

I bought a router from MTN Shop in East London, Hemingways. For a period of 12 months i should be getting monthly 1gb data. That has not been happening. I opted to purchase own data, but that also is not working. I have once bought 1gb data, and it took more than 5 phone calls to have it to reflect on my router. On the 29th March 2021, i bought 2weeks 2gig data, until this day that data has still not reflected. My worry is that when 2weeks expire i will also forfeit my data without using it.