Hello jigyasu mishra
The clientId you are using "\te6379e6b-7428-4063-8df4-dbf793b15da6" seems invalid.
I just created a service principal and the appId has 36 characters and no "". Even if we exclude "" from your Id, it still has 37 characters. If there is any particularity for Terraform, I am not aware of.
I would recommend you make sure the appId / clientId is valid. You may go to Azure Portal -> App registrations and try to identify it there.
Additionally, you may want to create the AKS cluster using Azure CLI. For example:
az aks create -g aks-rg -n aks --service-principal <appId> --client-secret <secret>
I hope this is helpful. If any clarification needed, let me know and I will do my best to answer.
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