Dupe corruption

[edshot99]

Describe the bug

I try to save a build and it fails to save.

The first time this happened it gave this error

[advdupe2] addons/advdupe2/lua/advdupe2/sh_codec.lua:434: attempt to concatenate field 'Class' (a nil value)
  1. CheckValidDupe - addons/advdupe2/lua/advdupe2/sh_codec.lua:434
   2. Decode - addons/advdupe2/lua/advdupe2/sh_codec.lua:512
    3. UploadFile - addons/advdupe2/lua/advdupe2/cl_file.lua:105
     4. DoNodeLeftClick - addons/advdupe2/lua/advdupe2/file_browser.lua:179
      5. unknown - addons/advdupe2/lua/advdupe2/file_browser.lua:1097

Assuming this was fixed and starting again I get this new error

[advdupe2] addons/advdupe2/lua/advdupe2/sh_codec.lua:434: attempt to concatenate field 'Model' (a nil value)
  1. CheckValidDupe - addons/advdupe2/lua/advdupe2/sh_codec.lua:434
   2. Decode - addons/advdupe2/lua/advdupe2/sh_codec.lua:512
    3. UploadFile - addons/advdupe2/lua/advdupe2/cl_file.lua:105
     4. DoNodeLeftClick - addons/advdupe2/lua/advdupe2/file_browser.lua:179
      5. unknown - addons/advdupe2/lua/advdupe2/file_browser.lua:1097

How to reproduce the bug

No response