Friend Time's prefix is "-ft" (note the dash symbol).
See the following guide on finding time zones.
If you are trying to set your time zone and keep seeing "User not found.", please see the guide on setting your time zone.
The following is an example of how to set your time zone:
Friend Time requires that you have Direct Messages enabled in at least one server that you share with Friend Time. Please check your Privacy Settings for the server.
Please check that the following are true:
The server's list setting is enabled.
There is at least one time zone in the server's time zone list.
Yes. Please see the set command for more information.