Apple Watch and DIGITS

¡Excelente pregunta! Fortunately, the DIGITS-type software is built into the watch already so you just have to make sure you've updated the EID (you may have to reach out to care or T-Force to confirm it's been activated) then go to the Watch app on your phone, select Cellular, then Add Cellular Plan.  Be sure to only do this AFTER you've confirmed the EID has been activated or else you may accidentally add a new line to your plan.

I have digits app on my phone, because I use it to transfer my work phone calls to my cell. I just bought an Apple Watch SE cellular. So I can take the phone calls without carrying my cell phone with me.

When I received phone calls trough the digits app my watch doesn’t ring only my phone.

I called T-mobile 4 times in one day  for someone to help me to fix this problem and was told the Apple watch won’t work with digits app even if it is paid with my phone.

Can you please help me? I talk to T-Force., Customer care,. Digits department. Nobody seems to know the solution. 
 The ad says it work with call and watch even if I don’t have the phone with me.