Unfortunately these values are not able to be changed once the VM is created. If you require changing these values you will need to recreate the VM. Details about this can be on the Automatic VM guest patching for Azure VMs page:
For Windows VMs, the property
osProfile.windowsConfiguration.enableAutomaticUpdates can only be set when the VM is first created. This impacts certain patch mode transitions. Switching between AutomaticByPlatform and Manual modes is supported on VMs that have
osProfile.windowsConfiguration.enableAutomaticUpdates=false. Similarly switching between AutomaticByPlatform and AutomaticByOS modes is supported on VMs that have
osProfile.windowsConfiguration.enableAutomaticUpdates=true. Switching between AutomaticByOS and Manual modes is not supported.
Sorry for the bad news. Let me know if you need more assistance or have more questions.
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