Fusion: Runtime Error - "[404] null with primary key value(s) "xxxxxxxxxxxx" not found" - Workfront Update Record module

Is anyone familiar with this error in Fusion that occurs on a Workfront Update Record module? I think I've seen it in the past in Fusion 1.0 when it was trying to set a value in a dropdown field where the value was not an option in the dropdown menu. This case, though, I am trying to update a simple text box field in the operation, and still getting the error. Any ideas what it might be?

I am attaching screenshots showing the logic for setting the value, the Inputs and the error. Any insights would be appreciated. Thank you.