Hi LeDuan,
Not all 4K Ultra HD TVs support HDCP 2.2 on all HDMI sockets. This is particularly true of older 4K Ultra HD TVs where HDCP 2.2 may only be supported on one HDMI socket.
On older Panasonic models (yours was made in 2015) you should connect a high speed HDMI cable on HDMI 1 or HDMI 3 or the HDMI labelled as 4K.
I suggest trying HDMI 3 first.
Also you may need to follow the instructions from the manual in picture 1
Picture 1
Have you got the latest software updates on your Panasonic? To check see picture 2 below.
Picture 2
From what I can see using Google your Firmware(software) version should be at least version 3252 in the format shown in picture 3
Picture 3
Dave
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