Meeting Rooms booking not working?
You need to exclude the meeting room resources from Xink ReRouting rule.
Login to Office 365 admin portal "mail flow" find Xink-Auto-ReRouting-Catcher and edit it as shown below.
Replicate the setting configuration below and then add all affected mailbox calendar and meeting rooms in sender and recipient. Lastly click Save.
Note: You may also apply this solution if you are getting bounce-back messages or having a problem sending or receiving emails on a particular service account or mailbox. You can you also exclude those mailboxes from getting rerouted by Xink-Auto-ReRouting-Catcher