This occurs constantly. If I clear the error and press the continue button in Studio, the H2D continues on its merry way printing my part as if nothing happened. I make sure the build plate is properly cleaned and wiped down with IPA before each print.
EDIT: I do not use gluesticks or any other type of adhesive so it wouldn’t be a lump of stick glue. Also, the H2D has not been modified in any way. I’m using the PEI build plate that was shipped with the printer.
Maybe the camera/sensor itself is dirty? No idea which one is used.
I agree with @technodanvan, my guess is also a dirty camera. It seems like the live view camera is the one used for foreign object detection from the docs (https://wiki.bambulab.com/en/h2/manual/intelligent-detection), so make sure that one is clear of any dirt/smudges and hopefully that should fix your issue
Make sure you have removed all of the foam packing from the inside. Had the same error until I discovered some packing I over looked.