Word Work- Funky Letters

So part of my word work are these letters. I used a box from Target and added letter stickers to the back. Here is the problem. There are all these letters that are misplaced- see lower left corner. Yes some are from the kids, but some of the compartment walls move.  I am not sure how to fix this.  If I put tape to hold it, then the letters will get stuck. :(

For your help, I am including this Word of the Week Frame.  Each week we have "Cool Tools" from PBIS. So from that, I choose a word from that topic and that is our word of the week.  I hang it on my focus board.