Pywal doesn't change the wallpaper

[Xpuck0]

*on Arch with Gnome and Xmonad

Yesterday I was searching the web how to setup and configure Arch. Pywal was one of the programs I installed after the setup. Everything was so clean and I really liked it. Now when I run wal -i (path to pic) pywal only changes the colors of the terminal but the wallpaper is still the same even though after running the command every output is successful. I was configuring my xmonad.hs file when the problem occurred. I switched to my default xmonad.hs file but it didn't work.
I don't think it is because of the xmonad configuration because I have the same problem in the gnome desktop. Now I'm trying to find a solution.

Edit: I just rebooted and now it works with gnome. It's probably in the xmonad.hs

[KiranWells]

What wallpaper setter do you use? If Pywal can't find one of the supported ones like feh, I don't think it can change the wallpaper.