I win a match in the arena and give a lose

[XavierDX-2314]

When I win the third match in the arena, the loser counter was 3 and I lose de arena.
I need help please. Thanks

[Rhasimir-1573]

Did you disconnect at any point, especially during the match finding step? There is a sticky post on this forum about common issues:

Hearthstone Common Issues

Here are some of the commonly reported issues that can be resolved. Unable to use specific cards in Adventure Missions Certain card effects are disabled while in Adventure Missions. This is to prevent them from trivializing all of the encounters. Some examples include: Mindbreaker Sideshow Spelleater Grizzled Wizard Golden Cards are not animating on mobile? After installing the Hearthstone app, mobile devices will need to download additional files which contains extra sounds and animatio…

This post links among other things to this article:
https://us.battle.net/support/en/article/17276?blzcmp=app