Error: Operation type [setMachineType] failed with message "e2 instances do not support onHostMaintenance=TERMINATE unless they are preemptible."

I received an email from Google on 20 Jul 2021 entitled:

[Action Required] To continue receiving your Free Tier discount, upgrade your F1-Micro VM to an E2-Micro VM by September 1, 2021

"The Free Tier F1-micro VM is changing to the E2-micro VM as the VM to use for free. On August 1, 2021, E2-micro Free Tier will be introduced. Follow these steps to change your machine type to E2-micro to avoid incurring charges for continuing to use F1-micro after August 31, 2021."

I stopped the affected machine instance, changed the machine configuration to:

• Machine family --> Series E2
• Machine type --> e2-micro (2 vCPU, 1 GB memory)

Saving the settings results in this error:

Editing VM instance "ubuntu-vm" failed. Error: Operation type [setMachineType] failed with message "e2 instances do not support onHostMaintenance=TERMINATE unless they are preemptible."

What steps to do I need to follow to change the machine type?

Thanks

You set the On host maintenance availability policy to Terminate. Change this setting back to the default Migrate.