Field Unavailable in Automations Criteria

I'm trying to set up an automation with the trigger being, "when a 'Task' is modified and the 'Time Spent' field changes, yet is not blank." However, under "additional criteria" where I'm trying to say, "'Time Spent' is not <<blank>>", the system refuses to include the field in the dropdown.

You can see in the attached image 'Time Spent' is second to the last in the list of "any of the following fields change." However, it's not in the dropdown below. Why would this be?

The 'Time Spent' field is searchable. It's a duration field.


Any insight is greatly appreciated!

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Ryan Farrington
Graphic designer, project manager, copywriter, engraver, internal Quick Base developer
rfarrington@experiencepinpoint.com
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