ClassNotFoundException: kotlinx.io.unsafe.UnsafeBufferOperations

I'm getting this error from using Kord in my Spigot plugin (Minecraft):

ClassNotFoundException: kotlinx.io.unsafe.UnsafeBufferOperations

ClassNotFoundException: kotlinx.io.unsafe.UnsafeBufferOperations

. I have all the libraries loading, including

kotlinx-io-core-jvm

kotlinx-io-core-jvm

which the error is from. Any clues what could be the problem?

ClassNotFoundException: kotlinx.io.unsafe.UnsafeBufferOperations - Kord