I changed my username and my when I /home it says i do not have an island. My new name is KnoCkeMdEd
my old one was TeH_kiLLeR97

 

Your island is out there, awaiting your return
You can ask a Red mod or Dark Red mod ingame to locate your island. Once you get to your island, make a bed and sleep in it. This will give you access to use /homes (Yes homes, with a s), it acts just like /home only this one has a fancy 's' attached~ Make sure that you also have a mod break any locks that you have on chests so that you can easily access your stuff! I would also recommend writing down the coordinates to your island just incase you need a mod to TP you there if you somehow break your bed and cant use /home.

 

If you change your name back to what it was originally you will get back to your island but if you still want to keep your name ask a mod. They will locate your island and you can set it as a /homes.