build platform doesnt raise during printing

[jensen]

did you clean the FEB (as you say the "clear screen") and the buildplate with 99% IPA before first print?
and how did you level the buildplate (like the Elegoo-YT-video)?

Hi,
no, I didn't clean any part with IPA, eventually, that's why there's a lot of surface tension causing this issue?
I calibrated the unit as indicated in the video: I moved it down with a loose head after I laid a piece of paper on the bottom. After reaching equally the very bottom I tightened the screws.