Magnifying search not working

Description

Hi All!
Search using a magnifying icon does not find some employees, but when you use “directory seach”, the search works correctly.

Mark the user in the channel with @ also does not work autocompletion.

If you start a chat with this user, then the subsequent search using a magnifying glass works correctly.

We also use KeyCloak - can this affect the search?

Thanks for any help!

Server Setup Information

Version of Rocket.Chat Server: 3.18.5
Operating System: Windows
Deployment Method: tar
Number of Running Instances: 5
DB Replicaset Oplog: +
NodeJS Version: v12.18.4
MongoDB Version: 4.5
Proxy: nginx
Firewalls involved: -

Any additional Information

Resolved via Drop Indexes - db.rocketchat_message.dropIndexes()