Sonarqube asks for sonar.pullrequest.key

[alexantonica]

Expected Behavior

Do the analysis and publish the report

Actual Behavior

Sonarqube asks for Parameter 'sonar.pullrequest.key' is mandatory for a pull request analysis

Plug-in version, SonarQube version, CI system, build type

Sonarqube 7.6 developer edition
Bitbucket plugin 1.3.0

This is how i run my analysis:

sonar.properties

sonar.projectKey=proj
sonar.projectName=name
sonar.projectVersion=1.0

sonar.host.url=https://sonar76.test.net
sonar.login=5407433f8ea81fe92826c84f7fddf52457df8f85
sonar.pullrequest.base=develop
sonar.bitbucket.buildStatusEnabled=false
sonar.bitbucket.accountName=user
sonar.bitbucket.repoSlug=sonarqube-pr-test
sonar.bitbucket.oauthClientKey=6UnqyW4GcHAKmyzjAa
sonar.bitbucket.oauthClientSecret=cFWZD3d3eKx8DgqRKHk574qDFYnyQ2Nq
sonar.bitbucket.branchName=task/test-sonar-pr
sonar.bitbucket.pullRequestId=1 
sonar.analysis.mode=issues

and in terminal

cd project/

project/
    - module1
            |- src
    - module2
            |- src
    - sonar.properties

sonar-scanner -Dproject.settings=sonar.properties