Cosmos Db output 绑定超时

Question

I have an Azure Function V3 dotnet 3.1 running on consumption plan with a CosmosDB output binding that do a simple query in Cosmos. Normally the query runs in a few ms but recently I have seen a few times that the query times out. From what I can see in application insights the query runs for 1.1 minute and then cancels, retry for another 1.1 minute and then fails the request with a System.Net.Sockets.SocketException.

I can't find any signs of issues in the Cosmos DB, no high RU utilization, no http 429. The query being run in the binding is:

SELECT * FROM c where c.id = {customerId}

This is the result of running the same query directly in Cosmos in the Azure portal.

Where should a begin troubleshooting to understand what is causing this issue?

[FunctionName("FindById")]
    public async Task<IActionResult> Run(
        [HttpTrigger(AuthorizationLevel.Function, "get", Route = "customer/{customerId}")] HttpRequest req, string customerId,
        [CosmosDB(
            databaseName: "customers",
            collectionName: "customers",
            ConnectionStringSetting = "CosmosDBConnection",
            SqlQuery = "SELECT * FROM c where c.id = {customerId}")]
            IEnumerable<ApiOrganizationCustomer> customers,
        ILogger log)
    {
    }

EDIT: I have now seen this behaviour on another Function app with another Cosmos DB. And this collection only have 4 documents to query. I can't see any other errors than the timeout.