Looking at the error "no common encryption algorithm", you are getting a connection but your browser does not support the needed encryption. Sounds like the browsers in the lab need to be updated. Another option might be if you are using a trial license VM, as that does not support SSL.
switch your browser and test again
The Fortinet Security Fabric brings together the concepts of convergence and consolidation to provide comprehensive cybersecurity protection for all users, devices, and applications and across all network edges.
Copyright 2023 Fortinet, Inc. All Rights Reserved.