Chromebook - chrome issues

Just bought a chromebook , need to sign and edit a lot of emailed pdfs , no problem downloading, signing or editing and they save perfectly on google drive, docs etc and re open perfectly but the instant I attach them to an email , outlook or gmail all the signatures and edits disappear. All works perfectly on my phone and a windows laptop but absolutely not on Chromebook. PDF extension for chrome in place and Adobe all working perfectly , only an issue on attaching to email

Any suggestions would be appreciated .... rather than ditch the chromebook LOL