I am wondering the same thing!

After renaming, make sure to Save.

Hi there, please try going to Map Editing → Room Partition, then select the area you want to rename and tap Rename. You will see a list of preset room names as well as a Custom option. If you want to set your own name, please choose Custom, enter your preferred room name, and make sure to tap Confirm afterward. Once confirmed, the custom name should appear on your map.