It looks like you might be utilizing the incorrect login credentials for your Ubuntu VM. I noticed that in example 1 and 2 you are trying different usernames. Please confirm the username you are using when you created the VM. The default username is azureuser
also can you confirm that you have setup the VM to utilize password login? If you are unsure, you can try resetting the password.
Hope this helps. Please let me know if you are still facing issues and we can troubleshoot with you directly.
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