Kings lost mine key

[Demon_Girl132]

So i have finished the story mode (on someone elses world in multiplayer) and I decided that I wanted to unlock some things in my single player world. I completed the altar which gives me the lost mine key for the gate to open.


I did not receive the key and I have no way of getting it again in the other world too (we all sold the key because we thought it was trash after unlocking the gate)

Do i need someone elses key to unlock it? Can the devs fix this?