Customer service incompetence and system shortfall

We have an MTN router on contract. I want to log in the MYMTN app to check data balance for that router and usage, which has an MTN number. It asks me for an OTP which is sent to the router. It is humanly and physically impossible for me to switch my fone off, take my sim out, put the sim from the router into my fone, retrieve the OTP, switch my fone off again, reinsert my own sim, and then continue with the login. Even more impossible if I want to check this balance when I am not near the router. I have been told that MTN, a giant in technology, is unable to send that OTP to any number other than the routers number.

Now I ask, how on earth do I check my data balance?

I also cannot fone 135 because the very clever customer service people refuse to help because the contract is in my husband's name.

I give up. I have a router and WiFi and absolutely Noone can tell me how to check my data balance.

Total incompetence.