@hussain Perhaps the server you update from didn't synchronize yet. Either wait a little more or change 'Download from:' to <Main server> in "Software & Updates" (with xenial-proposed enabled, of course).
@hussain Perhaps the server you update from didn't synchronize yet. Either wait a little more or change 'Download from:' to <Main server> in "Software & Updates" (with xenial-proposed enabled, of course).