The default interaction trigger is “On click/tap”. If you see an “On drag” trigger after creating an interaction, it usually means that an “On click” trigger has already been added to this object (look at the right panel). And, as you know, you cannot add two “On click” triggers to the same object, so an interaction is created with the next trigger.
It would be very helpful if you could attach a video of how you add the interactions where the right panel (Prototype tab) is also visible.