that is what I'm doing and when replace the new router with the old one the telephone disconnected and connect back again when I get the old router back or disconnect the new router

I already have a splitter and it connected within my old router and working fine

Hello I'm having new router AC 1200 or Archer VR400 when I'm trying to replace my old router with this router I'm directly losing my telephone connection what I'm doing is having direct line splited...