Hello, I can do first layer calibration using PLA and PETG on my Prusa i3MK3S+ well. However, when using the Colorfabb LW-PLA, the filament does not stick to the PEI sheet during the actual print. I have cleaned the PEI sheet and performed Z calibration many times but during printing of the first layer, either the filament did not stick to the PEI sheet or part of the first layer surfaces appeared to be scratched with holes and bits sticking up from the PEI sheet. Tried bed temperatures 50, 55, 60, 65C but issues remain. What is wrong?