Turbofloat server stopped working for no real reason

Good morning, we observed a strange fault of the turbofloat server at a customer's location : without any apparent reason the user could not use the license anymore, i.e. the activation of the server was somehow broken. They were neither able to deactivate nor activate by themselves until we deactivated the license from the web interface. They are running the license server on a VM (we are aware that there might be troubles if the VM is rebooted, but this was not the case here). Does the error message from the log file below tell you anything about the reason for this outage?Thanks a lot in advance!Best, Alice

2018-03-06, 18:21:03 <notification>: Extended existing lease (jm92181, 2). New expiration time: 2018-03-07 00:51:03 (in UTC).

2018-03-06, 18:51:03 <notification>: Lease has expired (jm92181, 2). Used / Total leases: 0 / 1

2018-03-06, 21:34:23 <error>: This TurboFloat Server is not activated anymore - exiting immediately. (Error code: 0x1). You must activate this TurboFloat Server via commandline like this:

TurboFloatServer.exe -a="ABCDE-FGHIJ-KLMNO-PQRST"

2018-03-06, 21:36:37 <notification>: Auto-detected 2 CPU cores; creating a thread pool that large.

2018-03-06, 21:36:37 <error>: Not activated (error code: 0x3). You must activate this TurboFloat Server via commandline like this:TurboFloatServer.exe -a="ABCDE-FGHIJ-KLMNO-PQRST"