Bitbucket server pull requests do not create a plan branch on Bamboo

[Sina Afrooze]

I am using Bitbucket server with Bamboo. I have a linked repository between the two and have enabled "create plan branch with pull request is created", but I don't see any plan branch created.

My setup:

Bamboo 7.1.2 linked with the following:

My bamboo setup:

And 

I see in the logs that bitbucket pull-requests are received:

2020-10-21 17:11:28,736 INFO [http-nio-8085-exec-23] [AuthenticatorImpl] Authenticated app 'Bitbucket:5482248460' as user 'null' successfully

2020-10-21 17:11:28,738 INFO [AtlassianEvent::0-BAM::EVENTS:pool-1-thread-12] [PullRequestAwareEventListener] Received pull request opened event [ part-recognition, from: refs/heads/VCVCOR-841-gtest_discover_tests, to: refs/heads/master]

but no pull-request plan branch is created and no pull-request builds happen.

[Sally S_ Miller]

does it work if you have it set to making the branch plan when a new branch is created?

[Sina Afrooze]

Yes, creating a new branch on bitbucket repo does result in a new plan branch to be created.

[Sina Afrooze]

I discovered that if I create a PR for branch of the same repo to master branch of the same repo, a plan branch is created. However if a PR is created from a fork of the repo to the main repo, plan branch is NOT created.