All of a sudden our Phone is not working, it says "Line In Use".... we have 2 Panasonic Cordless phones model number KX-TG6051AL both are not working, just getting a static sound cannot dial or receive phone calls. We also have a 3rd phone down stairs which is not a wireless & is also not working. We have the Internet as well but that is working fine as i'm writing this .
Have tried unplugging it all & re plugging in & also have tried a different phone.

Any other ways that i could try & anyone know a solution?

many thanks.