Ludicrously frustrating and nonsensical

I have tried to upgrade my router online. Now MtN and its delivery service provider (DSV) continues to attempt to contact me by calling my router, which obviously does not receive calls, only for them to send a sms confirming that they have attempted to call and that I must call them back.

It gets more frustrating when I contact DSV and they say they cannot assist me unless I call them from my router, ludicrous, right? Apparently, it is supposed to make absolute sense to MtN and DSV.

This is such a frustrating experience.