You can create a "Scheduled Job/Flow designer" that runs everyday.
1)Store the date/time of a problem record "Resolved" datetime.
2)Compare it with current date/time.
3)If the difference is equal to 14 days then update state value to "Closed".
Refer below links too.
https://www.servicenow.com/community/developer-forum/problem-auto-close-best-practice/m-p/1584988
https://www.servicenow.com/community/developer-forum/autoclose-problem/m-p/1670294
Mark it helpful if this helps you to understand. Accept solution if this give you the answer you're looking for
Kind Regards,
Rohila V
5x ServiceNow MVP
