Secondary over primary role

I am fairly sure this is some kind of bug

Recently in my ranked matches, I have been queued by my secondary role (mid) more often than my primary role (bot) In my match history, I do have more primary role games, but that is only due to the fact that someone occasionally dodges/not locking in or I dodge (being fed up with getting mid all the time) There has a be an explanation as to why this is occurring Also I do understand that I will play my secondary role eventually but it should not be so often