Weird member log in issue

I have a weird issue on my site, here’s a quick summary:
I’m using a membership plugin (Indeed Ultimate Membership Pro) to manage user registration, login and page restrictions.
The issue is that often after logging in, pages which are restricted do not seem to recognize that I’ve logged in. This happens randomly, sometimes on the homepage, sometimes on the user account page (instead of the profile page it redirects to the login page). Also, I use a plugin to change the login button text to show the username when logged in, but when this issue happens it doesn’t show it, but shows “Log In” instead.
Below is a link where you can see what I mean:

I asked the support team of the membership plugin to check it, but they didn’t reproduce the issue, so no help…
I have also tried disabling other plugins to see if there’s a conflict, but it didn’t help… to me it seems like some kind of a caching issue, but I don’t use a cache plugin. I can clean the browser cache, sure, but I cannot expect the users to do that.

Any ideas, has this happened to any of you before?

Thanks a lot,
Adam

• This topic was modified 6 years, 2 months ago by szaboadammeister.

The page I need help with: [log in to see the link]