Students unable to respond in private channels

In the past week, I have received a number of complaints from teachers of students added to private channels that were unable to create conversations in the private channel and/or respond to conversations started by the teacher. The only potential solutions I have been able to generate are:

• User (student) Signs out of Teams, quits and signs in
• Teacher removes student from the private channel and adds them back into the private channel

I have been unable to duplicate the issue in my testing. Any idea why this might be happening or other solutions?