I did have nozzle cleaned but my ptfe tube is totally melted and i lost the spare so i flipped it and it did helped a lot i have managed to print something without a fail but still only at high temperature 235C so i had a lot of strings so tomorow i will try to find the replacement i hope it will fix it

just came to my mind that I can try to check ptfe tube that goes to hotend I know those are a bit sensitive to heat even tho in Prusa Mini the tube shouldn’t be in a melting zone but mine is very old. It is the one that my printer comes with so maybe I should replace it. I will update you guys if that is the case.

Yes, I have tried that but it didn’t help then I tried to burn away everything in a nozzle with a flame so the nozzle was very clean and I think it helped a little but after a few minutes of printing PLA, I still heard grinding of filament.

Yes PETG is printing just fine. I have switched to PETG also from Prusament to finish the print which bugs me because I like the colour of the PLA I have better for this one.