Getting errors when trying to use importers on certain pdfs

[Lioncat2002]

When I am trying to load a pdf using importer.SetSourceStream,
I get the panic

panic: Failed to initialize parser: Failed to read pdf: Failed to to read pages: Failed to read kids: Failed to resolve page/pages object: Failed to read value for token: <<: Token is empty
goroutine 50 [running]:
runtime/debug.Stack()
        /usr/lib/go/src/runtime/debug/stack.go:24 +0x5e
github.com/gofiber/fiber/v2/middleware/recover.defaultStackTraceHandler(0x18?, {0x1007980?, 0xc000c86468})
        /home/kittycat/go/pkg/mod/github.com/gofiber/fiber/[email protected]/middleware/recover/recover.go:12 +0x26
github.com/LegalForceLawRAPC/notarysign/src/core/fiber.RunServer.New.func2.1()
        /home/kittycat/go/pkg/mod/github.com/gofiber/fiber/[email protected]/middleware/recover/recover.go:31 +0x72
panic({0x1007980?, 0xc000c86468?})
        /usr/lib/go/src/runtime/panic.go:914 +0x21f
github.com/phpdave11/gofpdi.(*Importer).SetSourceStream(0xc00094cf60, 0xc00041b790)
        /home/kittycat/go/pkg/mod/github.com/phpdave11/[email protected]/importer.go:95 +0x1a8
github.com/LegalForceLawRAPC/notarysign/common/utils.AddPageToPDF({0xc0008be000, 0x247b6, 0x2a000}, 0x3)
        /run/media/kittycat/Linux_files/work/Signmarkia-Backend/common/utils/pdf_utils.go:91 +0x137
...

This is the code I wrote
It just deletes a page from the pdf

func DeletePageFromPDF(pdfBuf []byte, pageNumber int) ([]byte, error) {

	pdf = InitGoPdf()
	importer := gofpdi.NewImporter()
	pdfReader := bytes.NewReader(pdfBuf)
	r := io.ReadSeeker(pdfReader)
	if r == nil {
		return nil, errors.New("failed to read pdf")
	}
	importer.SetSourceStream(&r)
	totalPagesOfPdf := importer.GetNumPages()

	for i := 0; i < totalPagesOfPdf; i++ {
		if pageNumber != i+1 {
			importedPage := pdf.ImportPageStream(&r, i+1, "/MediaBox")
			data := importer.GetPageSizes()
			pageWidth := data[i+1]["/MediaBox"]["w"]
			pageHeight := data[i+1]["/MediaBox"]["h"]
			pdf.AddPageWithOption(gopdf.PageOption{PageSize: &gopdf.Rect{W: pageWidth, H: pageHeight}})
			pdf.UseImportedTemplate(importedPage, 0, 0, pageWidth, pageHeight)
		}

	}

	var newPDFBuf bytes.Buffer
	_, err := pdf.WriteTo(&newPDFBuf)
	if err != nil {
		return nil, err
	}

	return newPDFBuf.Bytes(), nil
}

The issue seems to be happening randomly.
It works once on the pdf
and next time it fails on the same pdf

Here's a link to the entire code if needed
https://gist.github.com/Lioncat2002/f40306aba45ccafe39dcceca294f50dc