Shared Memory problem.. Export to ..

Hi Guys,

I am having a strange problem in Our production server.

We are doing like

EXPORT lv_user from lv_user to shared memory indx(XY) ID 'ZSCE135'

and importing it later

EXPORT lv_user TO lv_user  FROM shared memory indx(XY) ID 'ZSCE135'.

I have check in debug mode  the data is setting properly but when we fetch it is  returning different different values.

I think it is values of concurrent users.

Please help what will be the possible cause.

I fear only single instance is available in memory instead of multiple instances.

Thanks in advance,