Good morning, @AzharMyrzasheva ...
You've posted your question to the global Canvas Community website. This is not the official Canvas Support portal ... if that is what you are looking for. You may be able to contact Canvas Support directly by clicking on your "Help" menu on your left-hand side global navigation menu. Here is more information about that:
How do I contact Canvas Support? - Instructure Community
Since Community members do not have access to your school's Canvas environment or your course(s), I would recommend that you reach out directly to Canvas Support...especially since you are getting a message that a page is unresponsive. They may be able to help you by taking a look at your course more in depth with you.
Good luck! Let Community members know how this was resolved after you've spoken with Canvas Support. Thanks!