MTN likes locking people out of their phones for simply not having signal

I purchased a phone more than a year ago and got an MTN sim card with the phone (the phone was not purchased at an MTN store), now I am on a research expedition to the Southern Oceans (a place that does not have any signal) and MTN decided that this would be a great time to lock my entire phone, simply for not having signal. I cannot access any function on my phone. This is seriously interfering with my work, my research, and my personal life, I do not think that it should be allowed to lock someone's entire phone for simply not having access to signal. I am writing this review to warn any one who might be considering getting an MTN sim card, avoid it.