My free database is always stopped since the trial period has expired

Summary:

My free database is always Stopped since the trial period has expired.

Content (please ensure you mask any confidential information):

I doesn't use more than 20GB Space
I haven't more than 30 Connections
I didn't have no activity the last seven days

I can start the DB but after few minutes they stop again,

Version (include the version you are using, if applicable):

19c

Code Snippet (add any code snippets that support your topic, if applicable):