When sign into Realms on Playstation consoles the gamertag displayed in world (in the realm) is using value from PSN name instead of Microsoft Account gamertag as part of Xbox Profile.
However the Realm Stories still using the Microsoft Account gamertag correctly as expected.
This issue did not occur until 1.21.1 update.
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We're tracking this issue in MCPE-183073, so this ticket is being resolved and linked as a duplicate.
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