Which version of Unity do you use? If it’s Unity 2021.2, there might be a bug as multiple students had this problem. Please test this solution from the official Unity forum. Please report a bug to Unity via Help > Report a bug (in Unity). Maybe send them a screenshot of the problem and also let them know about the solution in their official forum which you tested to no avail.
At the moment, 2021.1 seems to run well. I have had problems with 2021.2, and other students seem to have problems with it as well. I’m waiting for Unity 2021.3.
I couldn’t find the older version you use for this course but I probably didn’t search long enough.
You can find all versions of Unity here:
I am also not sure if it’s only a textmeshpro problem.
According to your screenshot, there seems to be a problem with Unity, maybe with the Canvas component. We cannot fix that because it is part of Unity’s source code. You could try to disable/enable the Canvas component. Perhaps it’ll will recalculate the positions. And you could try to set the Render Mode to “World Space” as a temporary fix (if that fixes the problem).
And if nothing helps, try to install and use Unity 2021.1.28.