One boundary for shared work
Each workspace has its own accounts, requests, memberships and commercial state. Access to one never grants access to another. The same person can be an admin in one workspace and a viewer in another.
Switch deliberately
Before switching, save any draft you want to keep. Select the destination from the workspace selector and wait for the new context to load. Check the workspace name before making a change with consequences.
When access disappears
A removed membership or an expired session can make a previously available workspace inaccessible. Sign in again if asked, then select a workspace you still belong to. Ask an admin to review membership instead of sharing another person's session.