One email address blocked

My mother’s email address: @windstream.net was blocked by you folks for some reason. It is my only way of communicating with her because she is deaf. 

I have been calling about this for two days and drove 100 miles to check on my 86 year old mother because I hadn’t heard from her only to find that she had been emailing me but I was not receiving them. I am receiving email from all other address and her emails are in her sent folder. We are both using iPads and Mac mail. I have also tried my webmail and they are not coming to there either. We have checked and there is nothing blocked by me in my settings on either web or macmail and nothing in my spam. This is unacceptable. She has just gotten out of the hospital and I must stay in touch. I was told yesterday that this would be fixed in24 hours. It is 24 plus hours later and still no resolution. I have been a customer for 35 years and am really rethinking my loyalty. This needs to be fixed NOW. I need to be in touch with my mother. Please, please, please. Imagine if this was you!

***Edited to Remove personal information