Lost my private key - how do I add a new public key to existing VM?

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Lost my private key - how do I add a new public key to existing VM?

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Lost my private key - how do I add a new public key to existing VM?

I've already looked at https://docs.oracle.com/en/cloud/paas/goldengate-cloud/add-public-key/ however that doc only mentions how to create an SSH key for a new VM. I instead need to add a public SSH key to an existing VM so I can access it again.

Such a simple must have task but wasn't able to figure out from UI or Google searches how to do this... I must be missing something obvious?