I have the same issue in my home and outside? I can’t make a call or the calls break up. All of a sudden? Ever since I became eligible for an upgrade??? My guess this is just a coincidence?? I have a Samsung SM-G930V. When I reboot the phone I get great signal for a little bit then it drop to one/ two bars? Now I might be ok with it being the phone except my work phone (Verizon) does the same thing and it’s an iPhone?