Does "Call Forwarding" Work on stock Mashmallow?

Hi there,

Just noticed I can't active or deactive all kinds of call forwarding since upgreaded to mashmallow.

Xperia Z5 Dual / E6683
I get "Call settings error - Network or SIM card error." everytime when I access Settings - Call - <Your Operator> - Call forwarding
I get "Call forwarding - Connection problem or invalid MMI code." when I dial *#21# and all 4 kinds of MMI code.


Suspicions & Recent activities:
1. upgraded to mashmallow
2. subscribed a new 4G LTE plan and changed to a NFC SIM.


I'd like to know is that an individual case or everyone get this problem caused by stock mashmallow.

Thanks
H.W.

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