Hello @harshavardhanc,
I suspect that the problem is that CircleCI does not trigger a pipeline whenever a pull request is opened on Github.
If you push a commit to a branch on Github, CircleCI will trigger a pipeline which will then trigger a SonarCloud analysis on that branch. If you open a pull request for that branch afterwards, there will be no new CircleCI pipeline triggered, and therefore there will be no SonarCloud analysis of the pull request. The SonarCloud check will therefore not be satisfied.
If you push changes to an already open pull request, CircleCI will detect that there is a pull request open for that commit. In that case the SonarCloud analysis will run on the pull request, and it will satisfy the SonarCloud check on the PR.
Hope that is clear, let me know if you have any more questions.
Tom