Some users still seeing 'loser' version of A/B test

What might be happening here is that you and some of your users originally saw the “loser” version so they now have a cookie that puts them in that group, so you or some users will continue to see the “loser” version.

If you want to make it so everyone sees the “winner” version, then you can duplicate the content entry and publish that new entry. It will have higher priority and will not have an AB test running, so everyone will just get the same content.