I have owned a realm for a few months now and have had this issue before, however it always seemed to solve itself with a simple restart. Now I can't get rid of it and have tried just about every solution I have seen on the internet and none seem to solve it.
This is very frustrating and it seems like Mojang has make absolutely no effort to fix or even address this issue, I will be requesting a refund for my realm subscription and I recommend other users to stay clear of realms and use a 3rd party server hosting platform if you actually want to PLAY on your realm.
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duplicates 1
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This report is actually a duplicate of REALMS-6147. Please see this link for further details regarding your problem.
This seems like a technical support question. I recommend heading to the Minecraft Community Support discord server, where volunteers can assist you.