Function app is triggered by old events after deployment

Question

Hello,

we have EventhubTrigger function.

[EventHubTrigger("%EventHubName%", Connection = "EventHubConnectionString", ConsumerGroup = "consumer", IsBatched = true)]

After re-deployment of the function, we noticed that the function were picking up all old events.

We looked at a file in azure-webjobs-eventhub/evhns-xxxx.servicebus.windows.net/consumer.

Offset is "no offset" and it is not updating.

We have multiple eventhubs and all offset values are "no offset".

==Function app detail==

.NET Version: .NET 8 Isolated

Operationg system: Windows

Runtime version 4.34.2.22820

App Service Plan: S1

Microsoft.Azure.Functions.Worker.Extensions.EventHubs:6.3.1

host.json has no custom set up. All default values.

bicep is used for deployment. On deployment of function, consumergroup is also depoloyed.

I hope you can tell me what is wrong.