Disconnect from a network share
Run net use * /delete instead. This will remove all share connections, and force you to use a new username/password, unless you're on a domain joined computer
It sounds like what you're running into is Kerberos credential caching, which refreshes on a timed interval.
Try this, which will disconnect the map, and then purge the Kerberos list:
net use \\server\share /del
klist purge
klist by itself should show you currently active Kerberos 'tickets', that may be used.