The error that came to my side is “Post-processing of the image failed likely because the server is busy or does not have enough resources. Uploading a smaller image may help. Suggested maximum size is 2500 pixels” when uploading the image but there was a different error when uploading the pdf document.
Solution: I solved the problem by removing the single quotation character that was in the name of the file and has replaced it with the underscore character. Then when I uploaded the image or the document again, things work perfectly.
