It is now possible to increase the one-time password validity. The new option called "TOTP Tolerance" is located at RAS Console > Connection > Multi-factor authentication tab:

Note: The option TOTP Tolerance can be set in the RAS console starting from v18. Starting from v19.2, TOTP Tolerance can be set to Microsoft Authenticator.

Note: Google authenticator is set to default display name when it is configured from RAS Management portal.