i was invited by a partner who has MICROSOFT 365 and TEAMS app as a guest. an email address was provided so that they could set it up in TEAMS on their side. received an invite so we downloaded the FREE version of TEAMS app on our side. We enter the email address we provided them but we get an error to contact our IT administrator to flip the switch to give me access to Microsoft TEams. Our IT administrator does not recall his password. Also he had entered a cellular phone# as an authenticator which he no longer has in his possession. How can we reset the password for the IT administrator to be able to activate TEAMS.