Can't text while on the phone anymore !!

[Confused !]

While I'm on a phone call, I would send text messages but now I'm not able to do it anymore. What's the deal ?? I have an iPhone 6 Plus on t-mobile.

 

[Rob Phillips]

Welcome to iMore! Make sure you have "voice and data" selected under Enable LTE in Settings > Cellular

If that doesn't work it could be your cellular connection to T-Mobile. Have you recently moved or are you in an area where you're suddenly not getting an LTE signal?