Nighthawk AC1900 /R7000 phone service interrupted since install of new router

Since i have installed the new router my phone system has been droppping calls, incorrectly directing calls.  I have updated the new firmware.  I do not recall the type of router I had before but I was not having the problem. I have tried everything with my phone service company and they seem to think it has something to do with the router.  This is all the information I can provide.   I am not technically proficient  

Any help would be appreciated