Nozzle keeps bumping into the prime tower

Bambu Lab X1 Series Troubleshooting
1

Hello, I have quite high part (230 mm) and in random heights after filament change nozzle starts scratvhing the layers on prime tower, as its escalates to nozzle bumb into the prime tower and destroy it which cause belt skipping and destroy the print (it starts printing layers on different places). Can anyone help me?

I switch Petg for pla and vice versa, setting of prime tower are on attached picture.

0,32 layer hight

0,8 nozzle

Speed is very slow and filament is dry (+ it never happens on printed part, only on prime tower)
image

2

That prime tower is huge. Eliminate the prime tower, check the “Flush into infil and support” You may need to bump up the flushing volume that it dumps into the toilet to avoid contamination of the PETG - presuming that is the support layer break for the PLA