For a while, I had to enter a password and then get an SMS authentication code once every 24 hours to login to Teams. The problem is that cleared spaces don't allow any personal devices (there's no cellular service anyway with TEMPEST hardening) and the unclassified (NIPRNet) workstations are usually blocked from connecting to websites like Google Voice and some commercial webmail services. The authentication code would timeout after five minutes, and that didn't always leave enough time to exit building, get to my phone with cellular service somewhere, and then re-enter the building and return to my workstation with the authentication code. If you always worked at the same desk, you could set it up to make a voice call to that desk phone number for authentication, but I didn't always work at the same desk.
My own solution was to use my personal Google Voice number for the authentication code, have Google Voice forward those messages to my personal Gmail inbox, and then have Gmail forward those emails to my official DoD email inbox. (Our official email wasn't yet on O365 and only required our smart cards to login, which later became the method for O365 login, thankfully.)