This instance is unresponsive. Confirm that the OS and network are configured correctly

Summary:

After a scheduled maintainance by Oracle on the instance with description as

Oracle has scheduled a firmware update maintenance event on your instance(s).

after that maintainance i am facing issue mentioned below

OS is still booting

A running status reflects the status of the instance, not the operating system on the instance. If you just created the instance, wait a few minutes to give the OS time to finish starting.

I contacted the support live chat and they mentioned to post in community regarding this issue.