2 inspection lot for one order

Dear all,

For customer return, after doing  delivery  of the return sales order , in system 2 inspection lot is being created, in one all  details like sales order, customer number and delivery number is reflecting while  in other inspection lot   material document and customer  number is coming. This is happening only in customer return inspection lot.

Please note that we are using z inspection types.

Thanks

Vivek Varun