Hi @Carolexx,
I appreciate you for dropping by here in the Community. I'll share some steps to help you with your reconciliation concern in QuickBooks Desktop.
The system will not remove any reconciled transactions in a company file. Payments/transfers get unapplied only if a user undo the reconciliation process.
You can perform some basic troubleshooting to isolate and fix the problem. I suggest you start by running the Audit Trail report.
The report allows you to check a record of who makes any changes to the data file. If you have more than one person using QuickBooks, you'll be able to view the changes.
Here's how:
- Click the Reports tab at the top menu bar.
- Hover your cursor to Accountant & Taxes.
- Select Audit Trail.
For more information, as well as some steps on how to correct discrepancies using the Reconciliation Discrepancies in QuickBooks, I recommend the following article: Fix beginning balance issues in QuickBooks Desktop.
Drop me a comment below if you have any more questions or concerns about reconciliation in QuickBooks. I'll be happy to help you some more.