Yes, you can create an incident for a past date.
Follow these steps
Step 1:
From the left navigation menu, click on Incident.
Step 2:
Click on + Add Incident.
Step 3:
Select the past date and time when the incident occurred.
Step 4:
Enter the required information and click on Submit.
Step 5:
From the Incident Management page, click on the View icon for the respective incident.
Step 6:
The selected date and time will be displayed on the left-hand side under the Date section.