Make sure your Anti-Virus software is up to date, download MalwareBytes onto your computer, install it, reboot and bring it back up in Safe Mode.
Then run a MalwareBytes full scan of your system.
It’s all up to date. I also have malware bytes anti-exploit running.
Agree with previous poster(s) ... sounds like your browser had been hijacked and you’re being re-directed to a rogue website.
that’s Facebook