Currently the pause account doesn't stop workflows so if someone cancels or has a billing issue there messages will still be auto sent thus incurring more charges to the sub-account user and the agency. Seems the workflows all need to pause when there is a billing issue or cancellation.
Same with domains, why would there funnel/website still work when they haven't paid or cancelled? This should be part of the pause of a sub-account, just like any other web/funnel builder has