InvalidFontFormatException: No encoding found with name /PDFDocEncoding to use as base encoding

[ghosttie]

We're getting this exception when splitting this PDF:

UglyToad.PdfPig.Fonts.InvalidFontFormatException: No encoding found with name /PDFDocEncoding to use as base encoding.
   at UglyToad.PdfPig.PdfFonts.Parser.EncodingReader.ReadEncodingDictionary(DictionaryToken encodingDictionary, Encoding fontEncoding)
   at UglyToad.PdfPig.PdfFonts.Parser.EncodingReader.Read(DictionaryToken fontDictionary, FontDescriptor descriptor, Encoding fontEncoding)
   at UglyToad.PdfPig.PdfFonts.Parser.Handlers.Type1FontHandler.Generate(DictionaryToken dictionary)
   at UglyToad.PdfPig.PdfFonts.FontFactory.Get(DictionaryToken dictionary)
   at UglyToad.PdfPig.Content.ResourceStore.LoadFontDictionary(DictionaryToken fontDictionary)
   at UglyToad.PdfPig.Content.ResourceStore.LoadResourceDictionary(DictionaryToken resourceDictionary)
   at UglyToad.PdfPig.Graphics.BaseStreamProcessor`1.ProcessFormXObject(StreamToken formStream, NameToken xObjectName)
   at UglyToad.PdfPig.Graphics.BaseStreamProcessor`1.ApplyXObject(NameToken xObjectName)
   at UglyToad.PdfPig.Graphics.Operations.InvokeNamedXObject.Run(IOperationContext operationContext)
   at UglyToad.PdfPig.Graphics.BaseStreamProcessor`1.ProcessOperations(IReadOnlyList`1 operations)
   at UglyToad.PdfPig.Graphics.BaseStreamProcessor`1.ProcessFormXObject(StreamToken formStream, NameToken xObjectName)
   at UglyToad.PdfPig.Graphics.BaseStreamProcessor`1.ApplyXObject(NameToken xObjectName)
   at UglyToad.PdfPig.Graphics.Operations.InvokeNamedXObject.Run(IOperationContext operationContext)
   at UglyToad.PdfPig.Graphics.BaseStreamProcessor`1.ProcessOperations(IReadOnlyList`1 operations)
   at UglyToad.PdfPig.Graphics.ContentStreamProcessor.Process(Int32 pageNumberCurrent, IReadOnlyList`1 operations)
   at UglyToad.PdfPig.Parser.PageFactory.ProcessPage(Int32 pageNumber, DictionaryToken dictionary, NamedDestinations namedDestinations, MediaBox mediaBox, CropBox cropBox, UserSpaceUnit userSpaceUnit, PageRotationDegrees rotation, TransformationMatrix initialMatrix, IReadOnlyList`1 operations)
   at UglyToad.PdfPig.Content.BasePageFactory`1.ProcessPageInternal(Int32 pageNumber, DictionaryToken dictionary, NamedDestinations namedDestinations, MediaBox mediaBox, CropBox cropBox, UserSpaceUnit userSpaceUnit, PageRotationDegrees rotation, TransformationMatrix& initialMatrix, ReadOnlyMemory`1 contentBytes)
   at UglyToad.PdfPig.Content.BasePageFactory`1.Create(Int32 number, DictionaryToken dictionary, PageTreeMembers pageTreeMembers, NamedDestinations namedDestinations)
   at UglyToad.PdfPig.Content.Pages.GetPage[TPage](IPageFactory`1 pageFactory, Int32 pageNumber, NamedDestinations namedDestinations, ParsingOptions parsingOptions)
   at UglyToad.PdfPig.Content.Pages.GetPage(Int32 pageNumber, NamedDestinations namedDestinations, ParsingOptions parsingOptions)
   at UglyToad.PdfPig.PdfDocument.GetPage(Int32 pageNumber)
   at UglyToad.PdfPig.Writer.PdfDocumentBuilder.AddPage(PdfDocument document, Int32 pageNumber, AddPageOptions options)
   at UglyToad.PdfPig.Writer.PdfDocumentBuilder.AddPage(PdfDocument document, Int32 pageNumber)
   at ETR.BusinessLogic.Services.Concrete.PDFService.SplitPdf(Stream stream) in C:\Users\ghost\source\repos\ETR\ETR.BusinessLogic\Services\Concrete\PDFService.cs:line 132
   at ETR.BusinessLogic.Services.Concrete.PDFService.SplitPages(Stream stream) in C:\Users\ghost\source\repos\ETR\ETR.BusinessLogic\Services\Concrete\PDFService.cs:line 29
   at ETR.Controllers.DocumentCaptureController.CreateUploadedFileFromFormFileAsync(IFormFile file) in C:\Users\ghost\source\repos\ETR\ETR\Controllers\DocumentCaptureController.cs:line 166
   at ETR.BusinessLogic.Extensions.IEnumerableExtensions.SelectAsync[TSource,TResult](IEnumerable`1 source, Func`2 selector, CancellationToken cancellationToken)+MoveNext() in C:\Users\ghost\source\repos\ETR\ETR.BusinessLogic\Extensions\IEnumerableExtensions.cs:line 8
   at ETR.BusinessLogic.Extensions.IEnumerableExtensions.SelectAsync[TSource,TResult](IEnumerable`1 source, Func`2 selector, CancellationToken cancellationToken)+System.Threading.Tasks.Sources.IValueTaskSource<System.Boolean>.GetResult()
   at ETR.BusinessLogic.Extensions.IAsyncEnumerableExtensions.ToDisposableListAsync[T](IAsyncEnumerable`1 source, CancellationToken cancellationToken) in C:\Users\ghost\source\repos\ETR\ETR.BusinessLogic\Extensions\IAsyncEnumerableExtensions.cs:line 9
   at ETR.BusinessLogic.Extensions.IAsyncEnumerableExtensions.ToDisposableListAsync[T](IAsyncEnumerable`1 source, CancellationToken cancellationToken) in C:\Users\ghost\source\repos\ETR\ETR.BusinessLogic\Extensions\IAsyncEnumerableExtensions.cs:line 9
   at ETR.Controllers.DocumentCaptureController.SaveCapturedDocuments(List`1 files, Nullable`1 etrId, Nullable`1 recipientId, Boolean barcode) in C:\Users\ghost\source\repos\ETR\ETR\Controllers\DocumentCaptureController.cs:line 96
   at Microsoft.AspNetCore.Mvc.Infrastructure.ActionMethodExecutor.TaskOfIActionResultExecutor.Execute(ActionContext actionContext, IActionResultTypeMapper mapper, ObjectMethodExecutor executor, Object controller, Object[] arguments)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.<InvokeActionMethodAsync>g__Awaited|12_0(ControllerActionInvoker invoker, ValueTask`1 actionResultValueTask)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.<InvokeNextActionFilterAsync>g__Awaited|10_0(ControllerActionInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Rethrow(ActionExecutedContextSealed context)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.<InvokeInnerFilterAsync>g__Awaited|13_0(ControllerActionInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeNextResourceFilter>g__Awaited|25_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Rethrow(ResourceExecutedContextSealed context)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeFilterPipelineAsync>g__Awaited|20_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeAsync>g__Awaited|17_0(ResourceInvoker invoker, Task task, IDisposable scope)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeAsync>g__Awaited|17_0(ResourceInvoker invoker, Task task, IDisposable scope)
   at Microsoft.AspNetCore.Session.SessionMiddleware.Invoke(HttpContext context)
   at Microsoft.AspNetCore.Session.SessionMiddleware.Invoke(HttpContext context)
   at Microsoft.AspNetCore.Authorization.AuthorizationMiddleware.Invoke(HttpContext context)
   at Microsoft.AspNetCore.Authentication.AuthenticationMiddleware.Invoke(HttpContext context)
   at Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddlewareImpl.<Invoke>g__Awaited|10_0(ExceptionHandlerMiddlewareImpl middleware, HttpContext context, Task task)

50058.pdf

The user says they've used this PDF before without an error but I can't confirm that.