Timeout awaiting response with batch insertion mode

Hello,
I'm trying to insert around 10 millions hashsets into Redis, it works perfectly until around 6 millions than I can this timeout error.
Below is the error message and the code. Is there any improvement that I can do for the code?

StackExchange.Redis.RedisTimeoutException: Timeout awaiting response (outbound=316KiB, inbound=11774KiB, 9422ms elapsed, timeout is 5000ms), command=HMSET, next: HMSET RegistrationObject:EN14BLZ, inst: 1, qu: 3181156, qs: 0, aw: True, bw: WritingMessage, rs: DequeueResult, ws: Writing, in: 0, last-in: 2, cur-in: 215, sync-ops: 1, async-ops: 1, serverEndpoint: mkrs.redis.cache.windows.net:6380, conn-sec: 493.01, mc: 1/1/0, mgr: 8 of 10 available, clientName: (SE.Redis-v2.6.90.64945), IOCP: (Busy=0,Free=1000,Min=8,Max=1000), WORKER: (Busy=2,Free=32765,Min=8,Max=32767), POOL: (Threads=16,QueuedItems=0,CompletedItems=31687), v: 2.6.90.64945 (Please take a look at this article for some common client-side issues that can cause timeouts: https://stackexchange.github.io/StackExchange.Redis/Timeouts)

            var addTasks = new List<Task>();
            IBatch batch = _database.CreateBatch();
            
            for (int i = 0; i < data.Count; i++)
            {
                var serialData = RedisExtensions.ToHashEntries(data[i]);
                Task addAsync = batch.HashSetAsync($"{typeof(TFeature).Name}:{data[i].Key}", serialData);
                addTasks.Add(addAsync);
            }
            batch.Execute();
            Task[] tasks = addTasks.ToArray();
            await Task.WhenAll(tasks);

Start with the batch insertion loop and the RedisTimeoutException details in the issue, then read the linked StackExchange.Redis timeouts article. Reproduce the workload with progressively smaller batches and the shown connection settings. Done means identifying whether the timeout is reproducible client behavior or workload-specific, with a documented diagnosis and actionable next steps.