Can't find your workspace?
It is the name in the address you normally use — yourcompany.prcd.staging.phoenixnet.au. It will be in a bookmark, or in any email PhoenixNet has sent you.
If none of that helps, ask whoever administers PhoenixNet where you work — they set it up and they will know it. We cannot look it up from an email address, because each business on this platform is a separate system and we do not hold a list of who works where.