If you want to change a created SPOOL request owner’s name then you can do this easily from transaction code SP01 with the following steps…

Go to SP01 and select your SPOOL number which you want to change owner’s name

For our example this spool’s owner is user TEST01 , now double click the spool request

Now you can change the user name field , i am going to assign user TEST02 to this spool request and then SAVE

After that you can go back or search this spool request and as you can see now owner is TEST02