Theia Magic

The reason is because you have marked yourself "Online to Friends/Groups" only under your preference. By doing this, it hides your online status to anyone who's not on your friends' list or in shared group. Two options to fix this: 1. Unhide your online status under preferences- make so anyone can see whether or not you're online. Then, anyone pulling up your profile can teleport you. 2. Or, if the person trying to TP you uses CTRL+ALT+V, it will pull up administrator options. One of these options is it will "ungray" the teleport button, regardless of whether the person in question is actually online or not. Or if their online status isn't shown, such as yours, it allows them to TP you.