How to catch Catalina Don't allow exception

So when i run below code , i get Catalina User consent "Your App wants to access Documents folder"

do {
            //return [FileAttributeKey : Any]
            let attr = try FileManager.default.attributesOfItem(atPath: "/Users/catalina/Documents/Test.docx")
            var fileSize = att

r[FileAttributeKey.size] as! UInt64
          
            //if you convert to NSDictionary, you can get file size old way as well.
            let dict = attr as NSDictionary
            fileSize = dict.fileSize()
        } catch {
            print("Error: \(error)")
        }

Even when i click on Don't allow, still the API returns attributes and API never throws any error. How can i catch the exception here and redirect user to give permissions in System Preferences.