I see bagging blades listed but specify a different mower. Mine mulches fine with the factory mulching blades but generally spits out a bit of the leaves to the right side when bagging.
Honda does not offer a bag-only or single-blade option for the HRX; it has always been spec'ed to use twin-blades.
Might try changing the Clip Director to a different setting, or try adjusting the height(s) of the front and rear wheels. Both will change the suction profile, and can effect leaf collection performance.