Note 8 - Do I have something different here?

[JHBThree]

Looks like a test unit.
Please type in *#0*# in the dialer and take a screenshot?

Is just me or do those multiple openings along the bottom and top look like mini sensors?

How is the the Dual Camera setup? Does everything look normal there?

Also maybe get AIDA64
https://play.google.com/store/apps/details?id=com.finalwire.aida64

Take some screenshots in System (blur out you Serial before you post!)
Camera, Sensors, and Devices.

You may have a test mule that may have some interesting hardware that never made it to production units.

Morse code most likely. Encoding the ID for the device so they can trace it.

 

[Tsepz_GP]

Also, a message generated by AIDA

Yeah definitely a test device, I'd take it back ASAP, probably a late prerelease model, odd how they sent you that, the shop just have mixed them up.

Morse code most likely. Encoding the ID for the device so they can trace it.

Oh, I had no idea! Makes sense. Probably best OP took it back, who knows what other weird things will happen with it down the line.

 

[D13H4RD2L1V3]

It’s a pre-release version designed for testing.

I would suggest taking it back for a consumer version. How they even sold you that I won’t ever know...