Unexpected error when computing the force in the x direction
I am new to ANSYS Discovery, and I was attempting to compute the drag force experienced on a design my team created for the F1 in Schools competition. I received the following error, and I cannot figure out how to fix it, "Select one or more faces on wall location for Drag Force. (129 Faces)". I have attached a screenshot of the error to this question. Any help given on this matter would be appreciated greatly.