@Chandurkar, Varsha (GE Healthcare, consultant)
As per document, The virtual network service endpoints for Azure Key Vault allow you to restrict access to a specified virtual network. The endpoints also allow you to restrict access to a list of IPv4 (internet protocol version 4) address ranges. Any user connecting to your key vault from outside those sources is denied access.
Based on the error looks like, you have restricted access to a specified virtual network, but the client address is not coming from that authorized network.
Try adding the subnet as a valid network to access the Key Vault.
Hope this helps.
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