Retention Policy?

We have a Power App that automatically updates a SharePoint List with the expense information entered into the application and that SharePoint list is then used for reporting. However, it seems as though the list is automatically deleting entries? 

For example, we had employee A leave our organization. We attempted to pull all entered information from 2023 and for some reason they are no longer in the application or SharePoint site. Does that happen because the license was revoked for employee A or does that happen due to a retention policy? I am at a loss on this one because I know users are not able to delete items and no one on my team touched the List. 

Additionally, only entries from 2023 are missing/deleted. There are a few expenses that were retained from 2022. I checked a different employee (Employee B) that has left our organization this year and again, the expenses from 2023 are missing/deleted, but the 2022 expenses are still there for Employee B.