Hello @Esylenna, welcome to the forums!
Does the same thing happen if you host a cooperative session and your friend tries to connect?
Is your console connected wirelessly or through cable?
Have you tried to reset your router?
Would it be possible to test using a wired connection, just to dismiss this step as it has previously helped other users?
Do you have any similar issues playing singleplayer or online?
@Whitequeen Should the issue persist, please open a new topic stating your connection speed, ping to the server, whether your console is connected through wired or wireless, and confirming you’re attempting to join a private online server and whether other servers give you similar issues or not.
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