Contact Facebook customer service, if can’t block someone on Facebook.
Facebook comes with many features to make it easy to use according to you. Block is a feature of Facebook, where you can block any one of your friend list or any other whom you want. Once you do it, then that particular person not able to see your profile or any activity of Facebook. If you are not able to block someone on Facebook, then you have to confirm, you are connected with the strong internet connection, and you entered the correct name. If you still can’t do this, then go towards Facebook customer service to fix it in a faster manner. https://gettosupport.net/facebook-customer-service/