We can’t control the cellular coverage on campus, but all buildings would have Wi-Fi, so you should receive the push notification for Authenticator. If your Authenticator device is not connected to Wi-Fi but you are able to sign in on a computer, you should be able to use the six-digit passcode (OTP or verification code) instead of the approval of the push notification.
Select the “I can't use my Microsoft Authenticator app right now” on the login screen and "Use a verification code" on the next.
Tap on the HCC account in your Authenticator app to see the OTP.