It's not really Frontier calling you, it's a scam that is being run out of India. Thus, the heavy accent. Simply hang up on them when they call. Unfortunately, because they are not in the US and frequently use spoofed numbers, there is little you can do about them.
Scammers trying to get information.
Whatever you do, DO NOT say the word 'yes'.
They record that word and then stick it in another recording to make is sound like you agreed to some service/product.
I get a call from this number at least once a day. I answered the phone today and the guy tried to convince me he is from Frontier Communications and needs to update my listing in the phone book by tomorrow or else I will start getting calls for a doctor's office. I told him I don't have anything to do with the listing of the phone number and to stop calling. He got frustrated with my lack of helpfulness and said he was going to let me speak to his manager. After about 2 seconds, what sounds like the same guy starts talking and explaining what he wants again. He wanted my full name and for me to wait on the line to verify information over the phone by holding and pressing different buttons. Too weird for me and I just hung up at that point. After that he left me a voicemail saying my name over and over again.