Regular maps and locator maps have their names reset to default "Unknown Map". To recreate this bug name any map with an anvil in survival and place it in any storage type. After that save and quit and load back onto the world/realm. The maps now have their named changed to default but as soon as you move them into your inventory their names turn back to whatever you renamed them to.
MCPE-140446
Map names
Resolved
Duplicate
0
user-4215a
(Unassigned)
Unconfirmed
Xbox
1.17.11 Hotfix
Retrieved
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We're tracking this issue in MCPE-37740, so this ticket is being resolved and linked as a duplicate.
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