Hi Luc,
App configuration has some limitations and when you exceed the limitation you start facing throttling issue.
App Configuration stores have different request quotas based on their tier. Free tier stores are limited to 1,000 requests per day, Standard tier stores to 30,000 requests per hour, and Premium tier stores have no request limits, ensuring uninterrupted access.
Please see the following links for reference - https://learn.microsoft.com/en-us/azure/azure-app-configuration/faq#my-application-receives-http-status-code-429-responses--why
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