Can't acces Keypad during call (0.9.6.9)

Hi

When I'm in call screen and try to press the keypad button, it won't show up.
Everything else works. Contacts Speaker aso.
I need it cause I need to call a service hotline where I have to press the number 1. But I can't.

Or am I just not doing it right??

Take your Meizu out of the leather case, if you have one. It is the only way I found to fix it.

I don't have a leather case...
I had it plain in my hands, I pushed the button but nothing happened...
Anyway I finally called from another phone.... But I would like to use my phone and not having to organize another one when I need to input a number...