Database clean up on demand

Is there any way to issue a clean up on demand?
Im doing some test and when I remove a client I have to set the clean up for the next hour and wait.
I tried with urbackupsrv remove-unknown but I get a bunch of sqllite errors and it doesnt remove the old Client.
Im running 2.1.19 on a freeNAS jail.

urbackupsrv cleanup -a 0% ?

Thanks Uroni !
I found something similar here in the forums and the documentation:
urbackupsrv remove-unknown -u root

I was trying basically to test a server, then I have to create and delete the same client several times and didnt want to wait until clean up window.
Not sure if the cleanup command does the same as the remove-unknow , which is best to use?