Cannot display Zhuyin keyboard when using Apple Carplay in Pioneer headunit

When I first installed Pioneer headunit unit DMH-ZS9350BT,

I was able to select Zhuyin keyboard when using Apple Carplay navigation (Goggle Map) in Pioneer headunit.

However after doing a new firmware update on the Pioneer headunit,

the Zhuyin keyboard selection suddenly was not available when using Apple Carplay navigation (Goggle Map) in Pioneer headunit.

Checked both the language setting on the iPhone 12 and on Pioneer headunit DMH-ZS9350BT,

both devices are already set to display Traditional Chinese.

I went back to the car audio shop and asked the car installer why my Pioneer headunit unit DMH-ZS9350BT can no longer display Zhuyin keyboard when using Apple Carplay navigation (Goggle Map) in Pioneer headunit. The car installer checked and confirmed both my iPhone 12 and Pioneer headunit is correctly set but just cannot figure out why the Zhuyin keyboard selection was missing.

The car installer tried using the same iPhone 12 to connect to another Pioneer headunit DMH-ZF8550BT (which is a newer model), the car installer was able to select Zhuyin keyboard when using Apple Carplay navigation (Goggle Map) in Pioneer headunit.

Does anyone have the same problem like mine ?

Can anyone advise how to call out the Zhuyin keyboard on Pioneer headunit DMH-ZS9350BT ?

Thanks in advance !