Most Ender and Bambu owners I talk to do the same thing when the first layer fails: they add 5°C to the bed. Then 5 more. Then they buy a new PEI sheet.

Nine times out of ten the nozzle is 0.1 mm too high, or the plate is greasy, or they are printing PLA on a 70°C bed that is warping the corners off.

Do this instead:

1. Wash the plate with dish soap. Not IPA as the first move.

2. Live-level or run auto-level, then baby-step the nozzle down until the line is slightly squished, not round.

3. PLA bed at 55–60°C. PETG a little higher. Stop guessing with 80°C.

If it still fails after that, it is a Z-offset or a clog — not “the bed is cold.” That is the whole session I run in an hour.