Pixel map preview different than wall

So I am trying to do custom letters on my pixel wall, The files I am using are png.

When I run the file the letter appears on the pixel map preview, but not on my pixel wall in reality. I have tried running both a white and a dark version of the file, checked the scale, and tried with and without the effects layer on. I'm completely stumped. any guesses?

This is my first time working with pixel mapping.

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