My friends can't connect in my world.

Please check on parental control if multiplayer is activated. 
Awaiting Response 

A couple of questions, just so this doesn't get resolved as incomplete.

1. Are you using the dedicated server software, the in-game LAN play or Realms? If it's the second, your report would belong on the Bedrock issue tracker and if it's the third, it'd belong in the Realms tracker.
2. If it's the former, is the world imported from a single-player world/realm, and are you able to unable to connect to it when trying to connect via the friend screen or localhost?{{}} If both of these are the case, it could be that LAN play is disabled on the world side. You can edit this with a save editor to fix that.
3. If the former is true but you're able to connect to it on your own, it's likely that you made a mistake somewhere when port forwarding. Check your router settings, then try again.

These are just some things I've gotten from experience (apart from 1). Hope this'll help,

Cleaning up old tickets: This ticket had been set to 'Awaiting Response', but has not received a response from the reporter (~3 months+) so is being closed as Incomplete. If you feel this is still a valid issue then please comment, or create a new ticket following the Issue Guidelines which includes steps to reproduce the problem.

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