Duplicate image indexing problem

I work with images of letters (in buttons) which are placed randomly in a table. In order to find the word of each line
ex: 1st line DON
2nd line OSE
3rd line NOSE

I get stuck at the stage where when we switch the images from one button to another to find a good word (since I have certain letters several times)
When I select an E while testing the app, it sometimes takes another E into account, so move some letters out of their place by itself
How can I make it so that I can move any "E" without the other E's being a problem for me.

Because in all my application I will have several levels with double or triple letters.

Thank you in advance.

Please show your relevant blocks, and describe what is supposed to happen....

Here is a blind guess ...

You are using a for each item in list block where you should be using for each number from 1 to length of list block combined with select item number from list