Cannot create Pull Requests

Recently i faced an issue where when i tried to create a pull request, its get denied. then when i click the link of compare across forks ( please make that link a button). i had to manually change my intended branch again. after that i was able to solve the issue. please put your concern into this matter.

Some repositories are configured to only allow pull requests on specific branches (e.g. on development branches). Could that be the issue?