Can you clearly tell your problem.
SPA is area from where u get/put data while working with IMS DC.
If you are using SPA , ur first GU should be for SPA, & first ISRT should be for SPA, the next GU/ISRT should be actual segment.
what you were trying with SPA
in procedure division
CALL 'CBLTDLI' USING DLI-GU
first i issued a GU call fro scratch pad area and then GN call for getting message from screen, but i am getting the screen messages in SPA-IO-AREA in first call itself. and same thin happens while inserting into the screen, the messages i like to store in scratch pad area are displaying in screen