I can’t activate FB

Best Support
Sorry for my english.
I’ve been trying to set the FB option for a few days, it doesn’t work.
I keep getting the message:
“Your facebook user token has expired, please re-connect to continue using”
It keeps trying to create new token but it doesn’t work.
And FB also rejected the application, I did everything through your video.
I really don’t understand how to get it to work.

Can you help?
Regards Karin