Wrong branch was merged.

Hi,

Today i merged a pull request, but have found that merged result is different than i expected.

My repository: https://bitbucket.org/dismine/valentina\\
Source repository: https://bitbucket.org/ValentinaZhuravska/valentina\\
The pull request: https://bitbucket.org/dismine/valentina/pull-requests/131/fixed-issue-522/diff

We use mercurial. And before i never close source branch, but this time i decided to do it.
Also we do not use unique branch name for each new feature. If someone add new feature it use named branch "feature". Then merge it with my "develop" branch.

This time some how bitbucket ignored data from pull request, closed already merged branch and merged it again.