Hi Bradley,
To me it does sound like you have a damaged spot on the sensor. Zooming in on a phone camera is typically just a digital zoom since the camera itself does not have the mechanisms to move the lens in and out, this would be why it disappears when you zoom because it is essentially cropping out that spot.
On my old LG G4, it was just a case of removing the back of the phone, and undoing the screws that help the camera assembly in place. I am not sure if that is the same process on your particular device. That was just the case for me.
Best of Luck,
Drew.