I have an A1, I bought it in July, the 0.4mm nozzle, I've already tested it with a new one I have, but the problem persists. I calibrated the filament, lubricated the machine, adjusted the tension, used Voolt3D and Cliever filament it is a national brand of Brazil, and both still have the problem. The first layer comes out perfect, I changed the infill type, but it continues. I don't know what else I can do. All the other prints come out perfect. I made the Nike Air Jordan, 57 hours of printing, it came out perfect, but the top layer, which is a flat surface, doesn't come out well! The other settings are standard from bambu studio for A1. Someone know how to fix it? Please help me.

"failed to extrude ams a slot filament; the extruder may be clogged or the filament may be too thin" I have this problem in my Bambu Lab A1, its not printing, I have purchase and use for only 2 weeks, I have change the nozzle for 0,2mm and print the Lithophane, when its end, I changed back to nozzle 0,4mm and have this problem. How can I resolve this problem?

I have purchase the A1 Combo, and print the "Dinosaur T-REX Pencil Holder" but have print two Dinosaur and have the same problem, I'm having these lines, what's the solution for this? The print configuration is the author's, I didn't change anything, I had it print from my cell phone