Hello @AnujKumarSenPostNord-8149 ,
Welcome to the Microsoft Q&A platform.
Unfortunately, the message size cannot be increased to more than 1 MB size as this is the default maximum size in Azure Event Hubs.
Please find the below link for more clarification on quota limits of Event Hub:
https://learn.microsoft.com/en-us/azure/event-hubs/event-hubs-quotas
Hope this helps. Do let us know if you any further queries.
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