Pinned items rearrange themselves.

I pinned all my apps as tiles so they were in alphabetical order. When I go back to click on something the icons have moved around. Is this suppose to happen and if so is there a way to turn it off.? If I try to put them back the way they were it screws them up even more. If it's not possible to turn off, can it be a feature in new builds? Is there a way to clear all the pinned items without having to click on them one at a time. I have 24 pinned items and that's a lot of work.