2FA (Two-Factor Authentication) is supported for partner portal logins. If enabled, users logging in to the portal receive a 6-digit code by email, which they enter into the login screen. The code is valid for 20 seconds.
They can click Remember this device if they don't want to be re-prompted every time they log in on their trusted device.
Your supplier must enable 2FA on your portal. Reach out to them if you have any questions.