MPNS sending Unauthorized response 401 Registration has expired

Question

I'm getting

HTTP/1.1 401 Unauthorized X-MpnShimErrorDescription: Registration has expired

as a response of valid MPNS request with cert uploaded to dev center and properly installed to push server. What does it mean that "Registration has expired"?

According to this link https://msdn.microsoft.com/en-us/library/windows/apps/ff941100%28v=vs.105%29.aspx?f=255&MSPPError=-2147217396

the only reasons of 401 Unathorized are:

• There is a mismatch between the subject name of the certificate on the cloud service and the subject name of the certificate on the Push Notification Service.
• If the token has been modified.
• If the token is not valid for its subscription.

There is nothing about expired registration.