I need to know  how to use Tcoil  to access my land line phones in both ears SIMULTANEOUSLY!.  

I have poor cell service and depend on my landline.  The Marvel Tcoil did not work in both ears simultaneously. I was told by Phonak that the Paradise Tcoil will also Only work in 1 ear at a time.

Any suggestions?  I am still using my Audeo Venture 90’s tcoil works in both ears simultaneously