4 strongholds later and 2 different worlds. We started a survival world, found the stronghold and went to fight the dragon..end portal wouldn't work. Found 2 more strongholds in that world and neither of them worked. So because we were using experimental gameplay we figured that was probably the issue. We created a whole new world, finally found the stronghold and went to activate the end portal for the 4th time and it still doesn't work even without experimental gameplay. All done in survival. We always play local co-op. Split screen. This is absolutely ridiculous now. And the fact I can't find anyone else with these issues is puzzling. Xbox One X. Fix this problem already!!!!