After the maintenance last night, I tried going into my realm today and it gives me the message unable to connect to the world. I can access someone else's realm world though so I know it is not under going maintenance anymore. I do not know why I cannot log in anymore.
Thank you for your report!
We're actually already tracking this issue at MCPE-68318, so I will resolve and link this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
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