500 error reviewing spreadsheet docs

[saracarl]

I think this is Tom York's 500 error:

I, [2024-04-16T20:21:00.589635 #17032] INFO -- : Started PATCH "/indianaarchives/indiana-draft-enrollment-lists-of-1862/review/one_off/33946927" for 68.57.247.167 at 2024-04-16 20:21:00 +0000 I, [2024-04-16T20:21:00.591290 #17032] INFO -- : Processing by TranscribeController#save_transcription as HTML I, [2024-04-16T20:21:00.591547 #17032] INFO -- : Parameters: {"authenticity_token"=>"1QjNg80TqwfdrYiWUWQRSwmhOZ8M2fvVJBLEIwqn9aRcRjo1a4mfGeXP8ComObJ4mxhGTfLbAWoFgOGN76pgoA==", "page_id"=>"33946927", "f low"=>"", "quality_sampling_id"=>"", "page"=>{"mark_blank"=>"0", "needs_review"=>"0"}, "save_to_incomplete"=>"", "filter-brightness"=>"0", "filter-contrast"=>"0", "filter-threshold"=>"0", "fields"=>{"4532 "=>{"County"=>"Posey"}, "4533"=>{"Township"=>"Black"}, "4534"=>{"Commissioner"=>"John A Mann"}, "4555"=>{"Page Number"=>"6"}, "4531"=>{"spreadsheet"=>""}}, "user_slug"=>"indianaarchives", "collection_id"=

"indiana-draft-enrollment-lists-of-1862"} I, [2024-04-16T20:21:00.610046 #17032] INFO -- : Completed 500 in 18ms (ActiveRecord: 2.7ms | Allocations: 11364) F, [2024-04-16T20:21:00.615223 #17032] FATAL -- :
JSON::ParserError (unexpected token at ''):

app/models/page.rb:399:in process_spreadsheet' app/models/page.rb:457:in block in process_fields' app/models/page.rb:453:in each' app/models/page.rb:453:in process_fields' app/controllers/transcribe_controller.rb:132:in save_transcription' app/controllers/application_controller.rb:64:in switch_locale'