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The target branch contains commits that were not reported to sealights and the user merged from the target branch to the pull request branch

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Solution #2

validate Validate in their the CI server (Jenkins mostly, Bamboo…) + scm that the last commit from the SCM (target branch) was reported to sealights Sealights via a build.
If not, then initiate a build from both the target branch and then the PR branch.