My realm keeps going back in time and kick all player in the 1.21.4 minecraft.

Outdated versions are not supported.

How do i fix it then

1.21.4 is not considered an outdated version.
However, how long does it take for your realm to experience a revert in time and kick players. And does kick screen say anything specific when it kicked you out?

About once an hour. And it will lag so bad for 1 minute before it kicked us.( i already update it to 1.21.5)

@Thor Skjærven Rakkenes Any versions that are not the Latest Release (currently 1.21.5) and the Latest Snapshot (currently 25w17a) are considered outdated and will not be supported (unless the issue also happens in the latest versions)

@Lyvyrak Lim Does this issue still happen in 1.21.5?

Whoops, missed the last part about updating it to 1.21.5.

Yes it still happens in 1.21.5

my realm is constanly being rolled back over 1 hr of progress, on version (1.21.5) i can play for about 2 hrs and then this rollback happens and makes the realm nearly unplayable

Thank you for your report!
We're tracking this issue in https://report.bugs.mojang.com/servicedesk/customer/portal/2/REALMS-4224 , so this ticket is being resolved and linked as a duplicate.

That ticket has already been resolved as Fixed. Please check the Fix Version/s field in that ticket to see in which version this behavior was or will be fixed.

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