Hi Venkat,
There is no chance to activate one by one thru process chains when we have multiple request at dso level.
Rather than deleting requests, activate one by one by using prorgam - RSODSACT1 and pass last request id.
last request mean you have 10 request, form latest one to old, 10,9,8,7....1. you can consider bottom req(1) was last req and pass to above prorgam it will actiavte that one only. like that way you can reaming 9 request after the success of req1..
Time being you need to do manual. for next loads onwards, add dso activation process step to your process chain.
Thanks