Internet Sharing AT&T: Why isn't it working on Window Phone 520 after 8.1 update?

[WPCentral Question]

When I turn on Internet Share on my Window Phone 520 with 8.1 Os, carrier AT&T,
get the following message, :Connection not shared, to enable tethering on this device, I called AT&T and they are working on this it could be fixed in the year 2016. Any Help.

 

[James8561]

re: Internet Sharing AT&T: Why isn't it working on Window Phone 520 after 8.1 update?

ATT screwed up and now we've got to live without tethering

 

[aikidaves]

Is this problem specific to the 520? Internet Sharing on AT&T is working fine on my 920.