Unable to Display Variable Value in VBCS Validation Error Message

Hi,

In the Visual Builder Studio, we cannot see the returned values of the variables. We are trying to configure a validation rule for the Create/Edit Performance Goal Details page. For that, firstly we would like to see and understand the returned values from the existing variables / page parameters.

So we have a test like below :

There is no condition, just an error message which writes :

Summary : Error Message

Detail : [[ ' ERROR ' + $fields.performanceGoalsV2.ReviewPeriodId.$numberValue() ]]

We have set the Target Field as Goal Plan Name.

In this case, even though we have ReviewPeriodId for this page transaction, we still cannot view it when we preview the Error Message.