Hi @suba1987 ,
Welcome to the Microsoft Q&A platform.
Unfortunately, you cannot delete Azure HDInsight cluster after a period of inactivity.
I would suggest you to vote up an idea submitted by another Azure customer.
https://feedback.azure.com/forums/217335-hdinsight/suggestions/5663773-start-stop-cluster-hdinsight
All of the feedback you share in these forums will be monitored and reviewed by the Microsoft engineering teams responsible for building Azure.
Currently, if you want to delete the cluster after a period of inactivity, you need to use create on-demand Apache Hadoop clusters in HDInsight using Azure Data Factory.
Hope this helps. Do let us know if you any further queries.
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