New Members not getting access to protected content

This just started happening - not blaming the update because I can't be sure exactly when. Existing members log in without a problem. New members are not re-directed and getting protected content warning. My client is super upset and I have tried everything I know what to do. I am with WP Engine which uses force strong password plugin and in the past it has caused minor problems but nothing like this. I have granted access - HELP!!!
Paul H