eufy robovac dop sensor dirty error

My RoboVac 11S has dirty sensor error code, but sensors are clean. I also tried unplugging and plugging back in the battery but not the solution. Anyone else found a solution (besides the white paper and tape bypass) ?

You could check the mobility of the front bumper as well.
If its not really “mobile” it causes an error as well.

Thanks for the reply. The bumper feel free of obstruction, no obvious limitation of motion.