Automation not working as intended

Hi all,

I have a sheet in which I'm tracking installation dates of equipment (outside vendor) and have automation to fire off to ensure the necessary pieces all fall in line (in house), within a timely manner.

However, something must have changed in the last couple of weeks, because it's fallen on its face and I'm having to manage the automation, thereby making the automation useless.

The columns "Has Install Date" and "Ship Hardware Check" are column formulas, and the key aspects here.

Has Install Date

=IF(ISBLANK([Chair Install Date Actual]@row), 0, 1)

Ship Hardware Check

=IF(AND([Has Install Date]@row = 1, [Chair Install Date Actual]@row < TODAY(+7), [Chair Install Date Actual]@row > TODAY(-14)), 1, 0)

Then, I have a workflow assigned to flip the check box on "OK to ship hardware". This never happens when I am NOT looking at the sheet.

I have to delete the value from "Chair Install Date Actual", save, reenter the value, save, THEN does the workflow fire to flip "OK to ship hardware".

To summarize, the above worked, some time passed, and now it doesn't. How can I fix it so as to be largely hands off again?