Hope you are doing well and thank you for reaching out.
Are you referring to removing the Google Drive storage from the Acrobat Reader mobile app? If yes, please try the steps below and see if that works for you:
Open Adobe Acrobat app
Tap on Files > Google Drive
Tap on the three dots at the top right corner > Manage Google Drive Accounts > Tap on the minus sign in front of the Google account.
Let us know if you are referring to something else.