Hi @MatthieuFrellec-9414, really sorry for the trouble that you faced. Error '449' signifies transient error which should work fine if we try after sometime. I hoped that you are able to create the container now.
There are few ways we can monitor the resources and understand the issue. Please read through the below links: 1. https://learn.microsoft.com/en-us/azure/cosmos-db/monitor-cosmos-db 2. https://learn.microsoft.com/en-us/rest/api/cosmos-db/http-status-codes-for-cosmosdb 3. Check the service health of the subscription to know any outages, resilience and Azure Service Health. Refer to Link, it has a video tutorial to understand it more. 4. https://learn.microsoft.com/en-us/azure/cosmos-db/high-availability
If you are still facing the issue, please let us know.