Why is my Galaxy S8 Active acting up while charging?

[kklaws]

This problem just started a couple days ago. While charging the phone makes repetitive brief vibrations and the brightness goes up and down. Also, there's a new display with concentric dots radiating from the bottom middle of the screen. The phone is essentially not usable while charging. Why did this happen and how do I fix?

 

[SpookDroid]

Have you tried a different cable or charger? What about Wireless Charging? Sounds like the port is making a false contact and the phone just constantly connects and disconnects from power.