@sofy Yep, this fixed it. Thank you.

@robert @Sofy This solved the issue! I just excluded forums from my WP Fastest Cache and it works now. You guys are awesome. Thank you so much.

@sofy Thank you!. Yes, there was a plugin WP Security interfering with newly created accounts.

hmmmm I guess I can just display: none; the wpforo-menu where it shows Register and Login and use Ultimate member plugin for login. It's strange how i...

@martin Yes, thank you. I got it working already but I was wondering if it's possible to move that button to the front of homepage (Wordpress blog)?

@sofy thanks! this does the trick