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Solution:
You had to configure the policies within key vault in "access policies". For key vault all the permissions are configured in access policies.
Below article explains about the access policies in Azure Key Vault,
https://learn.microsoft.com/en-us/azure/key-vault/general/assign-access-policy?tabs=azure-portal
Please "Accept the answer" if the information helped you. This will help us and others in the community as well.