I created a table element in Jaspersoft Studio, but only the table part is not displayed in Preview.

When I checked the subdataset, I found that the data was not being retrieved, so I deleted $X{EQUAL,product_name,product_name} specified in the where clause and the data began to be displayed.

I have already set product_name (java.lang.String) in Parameters.

I think this might be because the product_name displayed in the Main Report has not been passed to the subdataset.

Please tell me the reason why the table element is not displayed and how to solve it.