Apparently you can't forward your number! – T-Mobile IP Relay Review

I need this app because I'm losing the use of my voice. I set my phone to forward calls to my relay number. Then I get a text from my grandfather saying he keeps getting an operator that says it's an invalid number. I call customer service and they said that forwarding isn't supposed to work. I'm ditching this for Apple's built in TTY service (if I can get it to work). What's the point of having a relay number if you can't forward your calls to it?! I guess Sprint's relay service is just a shoddy as their cell service!
Review by Matth3ous on T-Mobile IP Relay.