Ominous and regular vaults can't drop heavy cores and tridents in Minecraft Realms

My friends and I own a realm, I have played it for quite a long time and I have opened over 200 regular vaults and over 70 ominous vaults, and I didnt get either a trident or a heavy core. today I decided to check in a singleplayer creative world if the problem is the realm or the version of the game, and I have gotten about 1 heavy core for each 10 ominous vaults and 1 trident every 25 regular vaults.

therefore my conclusion is that the problem is with Minecraft Realms