microflow parameter order should be of type firstModule.customer

hi,

 i am beginer to the mendix platform i am working on getting started app with order and customer entities by the guide line of the link  https://docs.mendix.com/howto6/denormalize-data-to-improve-performance

so i am getting error microflow parameter order should be of type firstModule.customer  attaching is screen shot of the Moduler.

https://drive.google.com/open?id=0B01TOLewbWF2bEdodGQ5UTltZVk

Thank you