This message typically comes from the Partners' Liabilities Smart Worksheet found below Line 22 on Form 1065 p5-6. You can access this form using Forms Mode.
Within the worksheet, the total on Line E should be equal to the sum of liabilities on the balance sheet. Add Lines 16, 17, 18, 19a, 19b, and 20. Or subtract Line 21 from Line 22.
You might also review the liabilities entered for each partner in the step-by-step section for Partner/Member Information (under the Business Info tab).