Error when trying to update whonix-gw-16

When I try to update whonix-gw-16 on the Qubes Update window, it shows an error saying:

Updating whonix-gw-16

Error on updating whonix-gw-16: Command '['sudo','qubesctrl','--skip-dom0','--targets=whonix-gw-16','--show-output','state.sls','update.qubes-vm']' returned non-zero exit status 1.
whonix-gw-16: ERROR (exception No such domain: 'disp-mgmt-whonix-16')

salt / Qubes Updater / qubesctl / disp-mgmt are all Qubes specific tools. Whonix doesn’t develop these.

This is therefore a Qubes issue which I cannot help with.

Therefore this needs to be redirected to Qubes support as per:
What to post in this Qubes-Whonix forum and what not.