Hi @Momo. Welcome to the community.
FYI I moved your question to a new topic. It’s generally better to start a new topic for a new problem rather than adding to an old topic - shorter, dedicated topics are easier to manage, and problems that superficially look the same can turn out to have different root causes.
There’s nothing obviously wrong in the begin and end logs. The versions of the scanner and MSBuild both look to be new enough. However, it looks like the Sonar targets that were installed in the begin step are not being imported during the MSBuild phase.
Could you post the logs from MSBuild please? If the Sonar targets are being there should be build log output starting with "Sonar: ".