[SDPhantom]

The first thing that comes to mind is if you're reloading in combat, secure frames are unable to be changed or even set up due to the game being in combat lockdown. The only thing I can think of to correct this is have your addon try to detect if you're already in combat. If so, wait until you exit combat before attempting to set up your frames. If you're waiting for a specific event before loading your frames, you might try moving it to the base of your code so it runs before ADDON_LOADED fires. There might be a time restriction on how long after a reload the game client will allow you to set up your frames.