Please support my learner.

Recently, I have been experiencing a recurring issue when my learners finish their exercises. An advertisement appears and cannot be closed, forcing them to exit and redo the exercise from the beginning. This creates a very poor learning experience when studying and completing assignments on Liveworksheets.
If this issue cannot be fixed, it would be unfortunate that I may have to stop using an otherwise very good application that I have paid for.
Please help me resolve and improve this issue.