LCD was replaced now Auto brightness no longer works

recently had my iPhone 8 ios 11.2.5. LCD assembly replaced after being cracked and now the auto brightness will not work. the toggle is on for the auto brightness, I have also turned off the color filters and reduce white point. still not readjusting to any changes in brightness. I can use the slider to turn the brightness all the way down and place the sensor directly under a lamp and the slider wont budge to compete with the light. I performed a settings restore, followed by a full factory reset/restore, and still nothing. everything else still works but this one option and it is incredibly annoying.

I contacted the service center and they assured me that they reused the front ribbon assembly and only replaced the LCD. is this a problem with the phone or possibly an issue with the replacement lcd?

has anyone else had this issue once an LCD had been replaced?