Hello everyone!
It started just on May 4th.
You appear to be in the region where this service is not available. (8x80a40401)
I was wondering if this is a glitch that will be fixed in the very near future, or is it specifically blocking users from some countries. So far, most of the complaints come from Russia 
Please contact Xbox Support about this issue.
https://support.xbox.com/en-US/help/errors/error-code-0x80A40401
Error 0x80A40401 occurs when you try to access Xbox Live
You see the following error message when you try to access Xbox Live:
Service unavailable
This may mean that you’re in a region where this service is not available. There’s no workaround for this.How to resolve the issue
Solution
As part of our regular review of our exporting practices, we’re adjusting our service offerings in some regions to ensure that we’re compliant with government mandates. As a result, some services are no longer available in all regions.
For answers to frequently asked questions, go to https://www.microsoft.com/en-us/exporting/default.aspx.