It is different on each phone. These are the instructions for the Galaxy S7 Edge. However, you might want to consider just calling customer care at 611 to verify whether it is set correctly.Sent from Mail<https://go.microsoft.com/fwlink/?LinkId=550986> for Windows 10
It appears that T-Mobile did an update and turned off the short codes as default. My phone showed the short codes enabled but T-Mobile had it disabled. Customer care enabled and the problem is resolved. I don't know if disabling and then enabling on the phone would correct the problem.
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