I think the community needs some more informations.
Which layer is it? First or last? Filament, Temperature, Filament Profil, Build Plate Temperature, open or close Door/Lid…? Filament Kalibation and Bed Leveling before printing?
Is the filament dry and calibrated? Are you using Bambu PLA or generic PLA settings? The link has generic PLA.
I already saw similar first layers, but not in a Bambu Printer.
Based on your success with past prints (discarding filament calibration and other issues), I would first check if the filament is adequately conditioned (most likely cause). If it is ok, I would try a hard reset of the printer and restart the slicer (just to be sure). If the issue persists, I will move to the nozzle and extruder.
Hard to say for sure, but with most of the print looking good and only select areas looking bad, I would say its a partial clog (but could be an extrusion related like others said).
Someone asked it you printed it with the top off or door open? This may be important because a clog or partial clog could occur if the temps get close to 50C in the chamber. PLA softens at 60C, so if the chamber is 50-55C and the hotend is 200C its not unheard of to see the upper hotend with the fan, get close to or over that 60C mark. If it does, the PLA will not push down the hotend correctly and will clog a little. I normally don’t have to worry about this, but it is always a possibility. With just about anything other than PLA and TPU, its not much of a worry, because softening temps are much higher than the chamber air can really affect the filament. So when using these low temp filaments, be aware of the possibility.
