How to fix this error in sum function, thank you for your help

Change the formula to =SUM(K5:K20) if the total should include all amounts shown through row 20; the current formula stops at K16 and also includes the hidden rows 6–12.

The corrected formula is:

=SUM(K5:K20)

SUM accepts a cell range written with a colon and adds its numeric values.^1^

Why the warning appears

The displayed result, ₱42,478.00, is a calculated value rather than a formula error such as #VALUE! or #REF!. The yellow icon is Excel’s error-checking warning. In the screenshot:

• Rows 6–12 are hidden, but SUM(K5:K16) still includes their values.
• The formula ends at K16, although values continue in K17:K20.
• Excel may warn when a formula differs from the expected nearby pattern or appears to omit relevant cells. Select the warning icon to see its specific message and use Edit in Formula Bar if the range is unintended.^2^

If hidden rows should not be included

Use SUBTOTAL instead:

=SUBTOTAL(109,K5:K20)

Function number 109 performs a sum while excluding manually hidden rows; rows removed by a filter are also excluded. By contrast, ordinary SUM includes hidden values.^3^

Choose the formula that matches the intended result:

• Include rows 5–20, including hidden rows: =SUM(K5:K20)
• Include only visible rows 5–20: =SUBTOTAL(109,K5:K20)
• Intentionally total only rows 5–16: keep =SUM(K5:K16), select the warning icon, and choose Ignore Error if Excel confirms it is only a warning.

References

1. SUM function | Microsoft Support
2. Fix an inconsistent formula
3. SUBTOTAL function