Spawnpoint Bug

So I set a spawnpoint somewhere on a skyblock island using /spawnpoint @s ~ ~ . I tested my spawnpoint because I was building a server lobby and I was making the spawn. I went on to survival mode and killed myself. But when I respawned, I was in the void! It might be because I was on the Windows 10 Nether Update Beta, but something like that happened before I was on the beta.