I have an Att Galaxy S4. It's the MF3 version. I rooted it and it works fine but I want to revert to stock ROM. I know nothing about flashing Roms as I only tweaked the phone via modules. In any case, whenever I try to reset the phone, it goes into Odin Mode. It goes into mode when I try to go into recovery mode as well. Odin Mode is a nightmare. Any suggestions?