Hi shan_k!
I would recommend starting off by validating the scanning API calls themselves are working first, before troubleshooting their integration via Meraki Sandbox.
The validation can be performed with any HTTP server configured to receive JSON objects which returns the organization-specific validator as detailed in the introduction guide.
Also important to note are the differences between the V2 and V3 versions of the Scanning API, which can be found in this KB article.
Let me know if you have any further questions on this too!
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