Players need to link their Java and Bedrock accounts:
Join the Global Link Server on both Java and Bedrock:
IP: link.geysermc.org
Java port: 25565
Bedrock port: 19132
Start the linking process by typing /linkaccount on either the Java or Bedrock account.
A random code will be provided. Enter this code on the other account using /linkaccount <code>.
Both accounts will be kicked from the server with a success message once linked.