@Pavel yannara Mirochnitchenko, Thanks for the reply. For the first question, I would like to confirm if this is a newly enrolled device. for newly enrolled device, there is a 1 hour delay before the user's device begins receiving notifications when a helper initiates a session.
https://learn.microsoft.com/en-us/mem/intune/fundamentals/remote-help-windows#how-to-use-remote-help
For the second question, I would like to confirm if the sharer or a sharer's device isn't in the scope of a helper, that helper cannot provide assistance. Please ensure they are in the same scope.
Meanwhile, please check user's RBAC my permission to double confirm the permissions already assigned. And as I know, license applied needs some time to take effect. You can wait some more time to see if the result will be different.
Hope the above information can help.
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