Github. How to unmerge a pull-request merged into another branch by mistake?

Question

GitHub

Hello
. Such a problem, by mistake, a pull-request was frozen from the feature branch to the master branch, but it should have been in develop
There are three branches:
master
- develop
- - feature
How to cancel merge #2?

Answer 1

git checkout master
git reset HEAD^
git push -f origin master:master