Printing petg on the Bambu, it a rite of passage for many of us. Orca slicer calibration prints for petg on p1s, 0.6 nozzle. I never had that problem on my old ender 3. I remembered all I did there was to raise the temps and print as pla- so I copied the pla cooling fan settings to the petg profile in bambu studio, and got an instant improvement.