Elytra Disappearing

I have been playing and twice this week my Elytra has disappeared once the durability goes to 1. The first time it happened I was confused and thought it was a glitch so I got another one but as soon as the durability went to 1 it disappeared again. According to the game Elytras shouldn’t disappear and now I’m scared to play because I can’t have elytras disappearing all the time. And now also I have wasted 2 unbreaking and mending enchantments on those elytras that disappeared.