Hello, First- the 5 digit code has nothing to do with your TV. You simply plug the Stick into the TV's HDMI
port and select the port using the Panasonic remote's Input button (HDMI 1, HDMI 2, etc.).
The 5 digit code is a code you need to setup on Amazon.com using a PC to allow the Firestick to stream instant videos.
Here is the Amazon FAQ related to the code:
Forgot Amazon Instant Video PIN
Go to Amazon Instant Video Settings.
In the Your Amazon Instant Video PIN section, type a 5-digit number to set up your PIN, or click View/Edit Your PIN to change your current PIN.
Again this code is for Amazon to know that you are viewing videos on your Firestick- it is not related in any way to your TV.You could unplug the Firestick from this TV and plug into any other TV at any time.
Below is the Amazon page that explains the answers to frequently asked questions regarding the Firestick (The PIN is to stream Amazon videos- not to setup the Firestick to the TV):
If you need further assistance let me know. Please do not forget to click a POSITIVE RATING before you go- as it's how I am credited for my work. You can follow up at any time, at no additional cost.