@KarthicK Sekar Thanks for posting in our Q&A.
For this issue, we appreciate your help to check if there is not only one app in .pkg file.
In our official article, I find that if the .pkg file contains multiple apps or app installers, intune will report that the app is successfully installed until all apps are installed. We can read the following article as a reference.
https://video2.skills-academy.com/en-us/mem/intune/apps/lob-apps-macos#step-4---review--create
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