How do I get my MTN line to start working again

I want to become mtn canvasser

Mtn hynetFlex

My mtn line is diplaying no service thought it’s a new sim that I just bought but it ain’t working since I bought it but I can check balance

Please I really need your help my MTN sim card 08140377099 is not working anymore and I'm out of the country and that's my business line I can't wait until I return back to...