we are loading data from PSA to Write Optimised DSO, but only 1 requests is fetched though PSA is habing 15 requests

In psa we are having 15 requests,in dtp settings we are having get all request by request setting checked. It needs to fetch all the request from psa 1 by 1

but it is fetching only 1 request means old request from psa and not fetching any more request. what need to be done . Thanks in advance.