Re-install macOS

[Susja]

Hi,
I have MacBook Pro 2015 running Catalina.
I wanted to re-install it.
Using Disk Utility I erased everything from Macintosh HD drive and started to install new OS but hit the error:
The volume "Macintosh HD" on disk2s5 couldn't be unmounted because it is in use by process 670 (kextcache). Couldn't unmount disk. (-69888)
How could I fix it?
Thanks

 

[casperes1996]

Are you installing from Recovery, Internet Recovery or createInstallMedia device?

 

[Susja]

Hi casperes1996
I tried from Recovery first and get the error.
Then I tried to get into Internet Recovery ... but failed to get into right session ... not sure why ..
I will try today to download OS on USB drive on another MacBook ... maybe this will help.
Appreciate your offer to help ... but I'm not exhausted yet LOL

Thanks