Losing my rating in a live game of chess, my previous rating was 1538, after winning the next game my rating has not increased, but decreased to 1444.
Can anyone help where the loss of my rating?

Different time controls are rated differently. Your blitz rating is still 1538. Your standard rating is 1444, and it looks like that's the highest it's ever been, so it must have gone up.

You are right, thanks explanation

 After winning my game in a team match my rating of 1911 goes down to 1887. Can someone explain it to me.Thanks.

That one I don't understand. They're both rated, they're both 3 day time control, and you did win. I'd contact staff about that one.