Then go ahead and apply for your PGWP ASAP. Stop working until then and hope for the best. This is the only option for now. I think the Study permit becomes invalid after 90 days of graduation but status remains as long as its valid. So, you cannot study or work after 90 days. It's confusing for sure but you have limited options. Do what the lawyer suggests.
Yeah I already stopped working and can't obviously study cause I grad already.