VM has reported a failure when processing extension AzureDiskEncryption

I am running the following script:

$keyVault = Get-AzKeyVault -VaultName $keyVaultName -ResourceGroupName $rgName;
$diskEncryptionKeyVaultUrl = $keyVault.VaultUri;
$keyVaultResourceId = $keyVault.ResourceId;
$keyEncryptionKeyUrl = (Get-AzureKeyVaultKey -VaultName $keyVaultName -Name myKey).Key.kid;

Set-AzVMDiskEncryptionExtension -ResourceGroupName $rgName `
-VMName "myVM" `
-DiskEncryptionKeyVaultUrl $diskEncryptionKeyVaultUrl `
-DiskEncryptionKeyVaultId $keyVaultResourceId `
-KeyEncryptionKeyUrl $keyEncryptionKeyUrl `
-KeyEncryptionKeyVaultId $keyVaultResourceId

which is returning the following around 1 minutes of processing:

Set-AzureRmVmDiskEncryptionExtension : Long running operation failed with status 'Failed'. Additional Info:'VM has reported a failure when processing extension 'AzureDiskEncryption'. Error message: "Failed to send DiskEncryptionData, Check KeyVault inputs, ResourceIds and retry encryption operation".' ErrorCode: VMExtensionProvisioningError ErrorMessage: VM has reported a failure when processing extension 'AzureDiskEncryption'. Error message: "Failed to send DiskEncryptionData, Check KeyVault inputs, ResourceIds and retry encryption operation". ErrorTarget: StartTime: 3/2/19 2:10:59 PM EndTime: 3/2/19 2:10:59 PM

i have verified the values are all correctly passed to the set command and no nulls are being passed.

in this case OP needed to enable Key Vault for disk encryption, under advanced access policies.