No new gateway after re spawning and killing the dragon.

Hey, so I defeated the dragon in the end world and one gateway portal appeared. It lead to an island of only plants and Enders. So I read up on the topic and re-spawned the dragon with end crystals, killed the dragon and no new gateway showed up. What do I do to get new gateways to show up so I can finally find an end city!? I'm frustrated!! -Xbox one seed 8275753553745893855 I'm guessing I am version 1.11.2. Thank you.

Thank you.