I cant' read my old pdf on my new tablet

I bought a new Android tablet and I copied my old pdf in it. No problem with normal pdfs but pdfs with drm generate the error "document includes features not supported by this version of Adobe Acrobat".

I'm using Adobe Acrobat 23.2.1.26166 and I can't find anything else that asks me to enter drm credentials. How can I unlock my files bought years ago?

Thanks in advance

Stefano