Hello,
This is likely microsoft's overzealous incorrect password attempt lockout, it is usually triggered when there are multiple logins from different locations, and as you said you're attempting to remotely access a work computer which is not at your usual login locations.
I suggest trying to login again via incognito mode sometimes incognito mode can get you around the too many login attempts lockout.
To prevent this moving forward I recommend using two factor authentication with an authenticator app, this is the safest login method and will not lock you out compared to sending a code to your phone number.
Hope this helps,
JC