Review on Suncala Stainless Steel Digital Protractor with Advanced Functionality by Christian Byrd

Bought in 2019 and used about ten times. When I moved the ruler today, the readings didn't change. I reset it and it was off 2 degrees. I measured the corner and it was 2 degrees off my first measurement, I moved the edge out and back into the corner and it was off another 2 degrees again. I repeated this five times and the values changed within five degrees, and once the scale didn't change up or down when moving the edge. I changed the battery and the problem remains the same.