On Page 30 of the Payflow Recurring Payments Developer Guide it details the parameters for running an inquiry on a recurring payment. Below in the information:
TRXTYPE Specifies a recurring profile request. Must be “R”
ACTION Specifies action to take. Must be “I”
ORIGPROFILEID Profile ID of the profile to inquire about.
Profile IDs for test profiles start with RT. Profile IDs for live profiles start with RP.
Just in case you need it here is the Payflow Recurring Payments Developer Guide: