Nomorobo turns off and has to be reinstated

In the last 2 years I learned about Nomorobo and had a Cox support advise me how to set up. Sounded real good since we were getting 10-20-sometimes close to 30 annoying calls a day. Finally peace for a while until the calls started increasing again. Finally....upset again I called again and spoke with support only to learn that somehow my NMR was turned off. So she advised how to reset it, which I did. Peace again..., well for a little while...., just went in again today to find NMR is turned off again. WHY?????? 

Why does NMR turn off by itself? Is Cox doing updates that turns off this feature?? Guess I now know, if the calls start back up to look into this again.