How do I close Oracle free cloud account

Summary:

I want to completely close and delete my Oracle free cloud accout, but I am not able to find any link. I am not able to open a ticket.

Content (required):

I was experimentig with Oracle free account, but I don't need it anymore and I would like to close and delete it. However, I am not able to find a link to close it, and I'm also not able to issue a ticket (also can't find a working link).

Please help me close it.