Did you hear of room lists? What is a room list?
A room list is a collection of room mailboxes. Room lists are specially marked distribution groups that you can also use the same way you use ‘regul...
Updated May 21, 2020
Version 5.0
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Sergio_Jacomella We had a similar issue where "Visitor Use" appeared twice for us. However, I noticed with ours there was an extra space before the second filter option. I used the filter to find out which room(s) it was applied to and found that it was where we had added a space after the comma so "Classroom, Visitor Use" instead of "Classroom,Visitor Use".
It sounds like you more likely have found a bug so should raise a ticket with Microsoft support but might be worth checking for any hidden punctuation or formatting errors. Unfortunately it takes days for the fixed errors to be seen by the users once you have fixed them in exchange.
The_Exchange_Team - please add a function for us to be able to force a resync / update / reindex /etc so it doesn't take half a week to make changes.