fix: logic did not exclude the completed rows

[weiseng18]

Problem

In REF, the zero column check should only check below the completed rows. The
check was done for the whole column, so columns like [1 0 0 0] where the
first row has been fixed while working on the previous column would trigger
the 500 error.

Solution

Update the zero column check

Checklist

• If the branch was not created off latest develop, merge locally
• Using latest develop and master, do git diff --stat master while in develop branch. Ensure that the diff is not too large

Notes

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