How to unblock website from FaceBook
There is nothing more disturbing than finding out that your website has been blocked by Facebook. This often occurs with no warning because the principles that run to protect users from spamming and malicious websites are completely automatic. Facebook is a great & valuable business tool.
1. Open Facebook sharing debugger.
Run the site through sharing debugger.
If you website has been blocked, it will you a warning message like below.
2. You can check your website is blocked or flagged malicious with a site scanning authority like Mc Afee, Trend Micro, SucuriSiteCheck, Web inspector, Foregenix, Site lock Website Malware Scanner, etc.
3. Appeal your links through URLs appealing sections.
Post an Ad through Facebook, if it gets declined, appeal the Ad too & explain that your site is verified as safe by one of the authorities mentioned above.
If the appeal is again denied, re-appeal & write the same thing. If Facebook denies many times, then delete the campaign and make a new fresh one.
Do the same thing again.If accepted, your website is no more likely to be banned.
Register yourself as a Facebook Developer, and then post your issue in an related forum.