Join codes are not working for a student

One of our students was attempting to join another world from home. They have joined successfully in previous weeks, but couldn't join for some reason this week. We get an error message saying that "Join Codes are not available right now. Ask your host for their IP Address to join their game". However, only this student received this error message whilst other students seemed unaffected. When we use the IP Address, it says that it was "Unable to connect". You can see a screenshot of the error message below.

We have double checked that the same Wifi was being used as previous weeks, and nothing has changed about the Wifi security policies.

Things that have been tried so far are:

• Restarting the computer
• Deleting all metadata and logging back in
• Reinstalling Minecraft Education Edition
• Rebooting the Wifi network
• Connecting to a different Wifi network
• Removing parental security

The student was using a Mac with MEE v1.14.50.

Any assistance with this would be much appreciated. Thanks in advance.