RFx Response Surrogate bidding

Hi,

When I try to create a RFX response for the RX, Since the
Surrogate bidding is activated for that Bidder.

   Buyer try to create the RFx Response :

         -- The Reponses activity tab the ‘Response on behalf’ button is
not enabled.

    There is any specific role need to be maintained for the
same.

Kindly advice on the same,