Users sometimes disappear

[unowen1939]

The users have disappeared as shown in the attached figure.

Nothing is recorded in the server log.
There is no notification on the webhook, but the user is gone.
After investigating MongoDB.
Users have disappeared from the Users table.
But the user ID remained on the board.

-----Environment(Server) -----
Wekan 6.09.0
Meteor 2.2
Node 12.22.10
MongoDB 3.2.22
OS Linux 3.10.0-1160.49.1.el7.x86_64
Cpu 4 Memory 4GB

[xet7]

@unowen1939

Do you have Backup you can restore?

[unowen1939]

@xet7
Yes I have.
And restored it.
But it has already occurred twice.