I placed the four crystals around the original dragon platform. The dragon spawn sequence began and the original obsidian pillars were replaced with the new/modded pillars and crystals on top. The center was replaced with the building and the new center crystal configuration. I destroyed the outer pillar crystals. Then attempted to destroy the center crystals, which didn't work. I then got on here and your youtube videos to look for a solution. I tried the "/end_island reset" and "/end_island reset true" command. Both state the command is unknown or incomplete command. I also made backups and deleted the DIM1 and DIM_1 folder. The end island was there, but the dragon structures and my man made structures were gone.

What else should I do?