If you are referring to uncollected NSF Fees from the tenants, then you would be able to collect those by running Pay Management Fees under Accounting > Payables. Be sure to run it as of "End of Last Month" and then as of "Today". Once you run that function and pay those bills, go to the Accounting > Diagnostics page.
If you have remaining items under "Positive Balances in Additional Fee GL Accounts", then you will need to collect those funds by creating a payable to your management company, towards the property on the Diagnostics, and the same GL account and amount. Any items under "Negative Balances" are owed back to your owners. You can clear these up by entering Other Receipts under Accounting > Receivables. Be sure to check "Exclude from Pay Management Fee Calculation" > the remaining details are the same as the Diagnostics (property, amount, GL account, etc).
Then you will need to transfer the funds from your Corporate bank account back to your trust account and deposit the receipt once the transfer is made.