May occur when importing monthly bookstore charges when Amount imported into Student Billing is the dollar amount of the student's last month's charges but appears as a credit. 

On the General tab of the Load Transactions window, a date range is selected that includes the credit Adjustments made to the customer records to clear the customer balances last month

Select a date range that does not include the adjustment credits from the last time transactions were cleared on customer records.

To fix the issue permanently to allow for All Dates to be chosen when loading:

1. Load all transactions for all dates with no filters
2. Clear the Student Balances after loading transactions

This will prevent previous adjustments from loading in the future and will clear out all transactions attempting to load.

3. In Student Billing, adjust or delete and erroneous amounts on the student records