Logged in user is seeing another user’s details when viewing own profile

There is a thread with this problem where the solution is to disable cache. I’ve tried most of the solutions – like disabling plugins – I’ve also disabled the caching on the website altogether but still users are seeing someone else’s profile. It is happening to everyone but they are seeing the admin profile (me) or another profile linked to me. Anyone have a different solution to disabling cache?

I can’t provide a link because you need a password to access the site.