Value cannot be null. (Parameter 'key') System.Collections.Generic.Dictionary`2.FindValue

I am trying to convert PDF to SVG file but every single PDF I try I get the same error when calling the Save method. Here is the stack:
2023-07-05T21:17:51.260Z c4f9a188-b865-49a0-8f92-c4802a9ee5b0 info at System.Collections.Generic.Dictionary2.FindValue(TKey key) at System.Collections.Generic.Dictionary2.TryGetValue(TKey key, TValue& value)
at #=zgy_AhM4FwFgiuuIite5eP6e3O63mDT9pnw==.#=zREsVcf4=(#=zr6Z_7BA= #=zvANh05M=)
at #=z$5mF$54yN10EGY5efWwGT7o1oC$S2L172w==.#=zIz2huD_saJWP2.#=z5nx5_kXdRuet(#=zr6Z_7BA= #=zvANh05M=, #=z3nqIwgA=& #=zc6nNL3A=) at #=zv9DkyAzUBuhWbPJjmWkzITZrPqRpaORtmmxzqQc=.#=zAMcPU1ZVo5kL(#=zg6AKRCb$CKVyf4MdmaZt13dXK9F_ #=zAiA52cvNCqkC) at #=zBkLxzzasmOPjS9E1RfeNLhtwCvBle0dAeNWBy$9mePcG.#=zqigxvCV5U2yX() at #=zBkLxzzasmOPjS9E1RfeNLhtwCvBle0dAeNWBy$9mePcG.#=zg_0jiks=() at #=zYAHirs1pfoRGWySci3uzzvM056vzfEHgVsTpm0TyDXvX.#=zm0Cpfl4=(#=zYGDZ$rhe4Ua0ezEMN8datUFC58cY #=zn5FluYA=, #=zAVT_PM5qsUpKqNbRjkZoSjABKnWHeYeXiA== #=zqm6DKRg=, #=z41PQwlAXVF3C4xYRZatHFfdl_JysbDnqc0WyBc0nGAOP #=zkcgOsl0=) at #=zE1ySM7SVG35k3XQW3Ck_oV7d_9FQu51K2g==.#=zrjjnohU=(Int32 #=zNEYeNnU=, IList1 #=z93f1Uwsvgh1YvakGeQ==, #=zh1R9bKF46b5e #=z8pZAxYw=)
at #=zE1ySM7SVG35k3XQW3Ck_oV7d_9FQu51K2g==.#=zm0Cpfl4=()
at #=zhs9d_Pq8rUNhT48dXcLIpVg3XAWd.#=zcRRjP9F6hGrH(Document #=zn5FluYA=, #=z41PQwlAXVF3C4xYRZatHFfdl_JysbDnqc0WyBc0nGAOP& #=zq51fJdci2K3e7sXIoA==, UnifiedSaveOptions #=zXhVl28g=, Int32& #=zvUj4_D7AXB8l, Boolean #=zmTAWoV8=)
at #=znQySupZIL2u4XxyYv5xqQFGQpeII.#=zKRaoO4gez803(Document #=zeEbG3BUMwoUl, String #=zeFWPThDus4wv, Stream #=zYkaUiQk=, SvgSaveOptions #=zXhVl28g=)
at Aspose.Pdf.Document.#=zp0nLFuDb7z1v(String #=zeFWPThDus4wv, SaveOptions #=zXhVl28g=)
at Aspose.Pdf.Document.Save(String outputFileName, SaveOptions options)
I am currently on Aspose.PDF 23.6.0

@pnevesenchoice
Please attach a pdf document with which this happens.

d50ba6a7-be10-4914-bd0a-a22776e501b5 (1).pdf (1.6 MB)

This was one of the files. Some more information:
The files work on my windows machine, but they all fail on the linux environment. I dont have that gdip or whatever library installed on the linux environment nor do I have the windows fonts installed there. Are they required?

@pnevesenchoice
It’s good that you mentioned Linux now.
in this case, you should use the Aspose.Pdf.Drawing library (so that there are no problems with gdi + in particular) and yes - you need to load the package with MS fonts.
See also the information here How to Install Aspose.PDF for .NET|Aspose.PDF for .NET (in the end) and give it a try.
If it still doesn’t work, write here.