There is an error when I make a video call. Why is that?

video-call mobile cellphone cell-phone smartphone

When I make a video call, there is an error as shown below, why is that?

Notification of video call support
If T phone is set as the default phone, the video call function is not available.
If you want to use a video call, change the default phone app from the default app settings to the manufacturer's phone app.

2907 2017-04-11 Gentleman

A. 1

That's exactly what the description says.
It's because I set the basic phone app to T phone now.

Gentleman 9 years ago 0

A. 2

I make a video call, but the default phone app is set to T phone, so I run it.
But video calls are not supported on T-phone.
That's why it's not working.
You can go into your phone settings and change the default phone app to the original phone app.

Gentleman 9 years ago 0

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