Error on 'Modify' button in Account -> Asset view giving "An end of file error"

Hi,

We are creating a Modify quote from Account -> Asset view. Out of box w/f 'SIS OM Modify Products & Services Process' is triggered behind the Modify quote process. In modify, we have implemented one custom functionality.
Here we have implemeted one custom functionality as per customer requirement. Customer wanted that when we hit on Modify button then not only selected Asset should moved to new modify quote but they want all other assets which has same installation id of selected asset and all the assets which has blank intsllation id should be moved to new modify quote. Hence, to achieve this we added our custom step after 'Get All Asset' step which actually append other asset into the 'All Asset LIst' which we recived in vanilla step.