I am using process builder for my opportunity record. I wish to add a criteria in process builder to define the criteria for the action group. In set conditions sections I select a field from the opportunity object and click choose. I get an error as show in the attached screen shot. I am unable to add any of the fields to the set condition section.
This happens often. Process Builder is nice and buggy. Keep trying and it should work. Sometimes you have to close out of the page. I usually see it going away after 3 or so attempts. If you continue having issues check the FLS of the field just for safe measures, though it shouldn't have an affect (had it error a Flow from being saved once).