Convert Base64 from SAP to file (Word, Excel) gets corrupted

Dears,

We have a webservice that sends Base64 to third party system. However, the file gets corrupted when downloading.

After researching for a while we found out that numerous users have the same issue with no clear solution on how base64 converted to this file(doc, word)

PS: it works fine in .pdf, .txt, .png

I would really appreciate your help

Best Regards,

Mahmoud