It seems at one point you reorganized your retainers. retainers by default appears in order of when they were obtained. this is extremely important to note if you buy like 4 additional retainers at the same because you need to make note on what order they showed up in incase you do reorganize them o i learned by clicking on the gear icon you can reset any sorting you may have done on the retainers. I have done this before and forgot to resort my retainers and locked myself out of my horde of materia and about 75 million on one retainer lol. I feel your pain on that. I do wish they listed the retainers name on said retainer option when you go to cancel additional retainer subs on the mog station.