@VadimSlutskyVadimSlutsky-7574,
Which product do you use? Skype or Skype for Business?
Here we are mainly responsible for Skype for Business. If you mean Skype, this community would be a proper site.
If you mean Skype for Business, I want to confirm several questions with you.
What changes do you do before this issue happened?
Does anyone else have the same issue?
To know your problem clearly, please provide us a screenshot if possible.
Besides, you could try to clear the client cache and make sure your client is the latest version.
If the response is helpful, please click "Accept Answer" and upvote it.
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