'Not Submitted' Expense Report Missing

Summary:

We have recently had a few cases whereby an employee has a large, unsubmitted Expense Report containing many expense items. All of a sudden, these expense reports and all the expense items within them seem to have disappeared and I am unsure on the reason for this.

Content (required):

In one example, an employee had an expense report that were still adding expense items to, that was created on 19/08/2022. This week they have logged in to find it gone.

I am unaware of any in-system functionality that would cause this unsubmitted claim to suddenly be deleted. If there is indeed this logic, then please correct me.