Cannot disable automatic updates for Adobe Acrobat Pro DC on mac

Hello,

When I go into Acrobat's preferences, I scroll down to "Updater" I untick "Automatically install updates".

Then, it asks for the admin password to "Install a new helper tool" (which it asks for every time I change preferences) which was entered perfectly well.

I click OK. When i reopen the pereferences, auto updates are ticked again by irself, as if the preferences never saved.

Any ideas? This broke the app completely last time, the auto update.

I tried deleting all preference files for adobe acrobat with this guide:

https://forums.adobe.com/thread/1595848

Then redoing all the settings and disabling updates, but it didn't work. The box always ticks itself again.

Anyone have a hosts list for adobe update servers? That box will not untick itself even after a reboot

Important:

I know disabling updates is not ideal but I really need this app to just work for the next few months

My os is macOS El Capitan 10.11.6. I can't update any further sorry because the mac becomes very slow.