bad band or frequency, see 'wireless info' for supported channels (6)

When I select a frequency for th 2.4 net I get the error:

bad band or frequency, see 'wireless info' for supported channels (6)

I wonder what 'wireless info' for supported channels (6) is exactly. There is no link to anything.

/interface wireless info allowed-channels

Google was my friend...

Can you please add some context like device, config and command causing this error?