Rosetta 2 installation on M1 MBP fails

I'm trying to install rosetta 2 via command line, using this command:

/usr/sbin/softwareupdate --install-rosetta

Source: https://derflounder.wordpress.com/2020/11/17/installing-rosetta-2-on-apple-silicon-macs/

The problem:

I'm receiving this error:

softwareupdate[981:12251] Package Authoring Error: 001-79711: Package reference com.apple.pkg.RosettaUpdateAuto is missing installKBytes attribute

Terminal screenshot:

The question: How can I get rid of this error and install rosetta 2 properly?

Don't know about the error message but the command also reports Install of Rosetta 2 finished successfully. So to check whether Rosetta actually got installed

• Install an "old" application not recompiled for M1 yet (if you don't have one, any free application from the Store which hasn't been updated since May 2020 will do)
• Run it to see if it works.

You can then also check in Activity Monitor by enabling the "Architecture" column there. If any process shows as"Intel", Rosetta is installed