I’ve raided the Elite Campaigns multiple times, but the game always resets it, so I can’t complete the daily quest or the prize wall mission because of this glitch, and I also lose any loot or experience I’ve gained from it.
They do work if you play with the elite stage regularly instead of raiding.
This has been mentioned before in “5.7 Known Issues” already, and there’s an announcement in-game acknowledging this issue. It’ll be fixed soon. Also, you don’t have to go through a fight for Elite Campaign levels in order to keep the rewards. You can raid each individual level at max without having to do it again. The only way you can’t keep the rewards is if you raid all levels of a hero.