when you start playing inverted spire it may work as usual till you defeat the boss, after that you cant open the chest or collect the loot and the mission doesnt end, if you wipe you get back to the first floor of the boss fight, plant the flag and go down, theres about 3 or 4 vex which you can kill after that theres nothing else, this happens if you go into strike via the vanguard ops tab, not through the portal(i believe it isnt in the portal as of now), this has been happening at least since the edge of fate came of, maybe earlier but i cant confirm that, i play the game on pc, maybe its happening on other platforms, but at least its happens on pc, i play with crossplatform enabled, so maybe it is possible that is happening everywhere or maybe one platform causes the problem then it extend to other players on crossplatforming