First could you please explain the workflow that you follow to convert the pdf to word?
How you have been doing it? Was it through the Adobe Reader DC desktop application or via https://cloud.acrobat.com/exportpdf
If you have tried online, then you must try it with the desktop application Adobe Reader DC Adobe Acrobat Reader DC Install for all versions
Also, go through the help document Text is garbled in converted file | ExportPDF
Let us know if it still doesn't work.