Fuse Import Sketch file error

Fuse version 1.2.1 (build 13974)
Mac OSX 10.13

When I run “fuse import mobile.sketch” I receive the following error

fuse: unhandled exception: Could not load type ‘Outracks.Fuse.Import.ImportOperation’ from assembly ‘Fuse, Version=, Culture=neutral, PublicKeyToken=null’.
at Outracks.Fuse.Program+c__AnonStorey0.<>m__B () <0x5df2180 + 0x0001b> in :0
at System.Lazy`1[T].CreateValue () <0x5df1ad0 + 0x001a4> in :0

What Sketch version are you using? Could you provide the sketch file that has the problem?