70+ year old clients require connectivity during COVID shut down.

This is an urgent plea, considering the current situation in the country. My elderly parent's cell phones were cut off in January because MTN said the payment was late, even though they had paid the account. They have been trying since January to resolve this issue and even paid early in February so that they would be in credit. To date, the issue has still not been resolved, and their phones are still disconnected. They have already been to MTN Sandton twice, and MTN Nicoleway three times. As they are 70+ years of age, I don't feel that they should be leaving the house to try and resolve this issue, and we would like to ensure that they have their cell phones on during the COVID shut down. Please will you let us know how we can resolve this as soon as possible?