acrobat reader won't covert pdf to word docx

Adobe Acrobat Reader DC doesn't convert files, it is just a PDF viewer without PDF file editing capabilities; you may need a paid subscription of Adobe Acrobat Pro DC (full desktop version) to convert files.

See the comparisson chart betweeen the two products: https://acrobat.adobe.com/us/en/acrobat/pdf-reader.html#tt

So I am still unsure how is it that you claim this used to work before in your phone because Adobe Acrobat Reader DC (desktop computer free version ) is not the same as the Acrobat Reader mobile app.

To convert or save a file to another file format using the mobile app you still need a paid subscription of Adobe Acrobat Pro DC to unlock those editing premium features in your mobile device.

Would you mind clarifying the workflow that you're trying to achieve (or have achieved in the past); it seems like I'm missing something in order to understand your issue.