One day i was at an enderman spawner when the endermite i use to attract the endermen either randomly died or despawned (it was named with a tag) and since then i've been unable to put endermites in minecarts. i've even placed an endermite in a 1x1 hole together with a minecart but it still refused to get in it. I've also tried boats but endermen just got in the boat with the mite and either killed it or it despawned again.

Did something change i don't know about or am i doing something wrong?