I have the same issue right now as well. First, I tried looking for another primary I could swap out, but unfortunately I had no luck. My next thought is to possibly incubate the primary antibodies with secondaries before IFC so that I create primaries with secondaries already attached. I could also purchase this already made (my target primary with an Alexa Fluor conjugate attached), but I have no previous experience with this and don't know how well it would work when primaries will have matching hosts. I would love to hear if anyone else has tried this or what other techs did to get around this.