To apply fines for damages to a current liability account for a security deposit in QuickBooks Online, you need to create a Journal Entry to transfer the funds from the liability account to an income account.
We recommend consulting your accountant before doing any method to ensure your financial records are accurate and compliant with all relevant laws. If you don't have one, you can find an accountant here: QBO Find an Accountant.
Please feel free to leave a reply if you have additional questions in QuickBooks Online.