@Kaki Sai Sudharshan (iCORE-CIS)
You are trying to fetch details from PowerBI through API, and the list you are seeing is only limited to 50.
This is because your nextLink response parameter might not be processed correctly which might be resulting in incorrect results.
Incase you are not using the nextLink property please check this document this is the cause and you can fix this issue.
Here is a similar issue on stackoverflow for your reference.
Hope it helps.
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