What bed temps are you trying? In general wmgeorge64 is right about increasing the bed temo. Searching the Internet, people seem to have good luck between 85-120C on kapton… With PEI maybe start at 100C?
You could also try getting the nozzle closer to the bed also. After using a business card to calibrate an initial nozzle height. Some slicers allow you to enter Z-offset to get the nozzle closer to the bed. I’d be very conservative and start with .1 up to .3.
Sorry I don’t have actual experience printing Polycarbonate… Hope to one day, though.
Edit: Looks like LB sells the filament and has some recommended profiles on the “Specifications” tab: