Facebook – Can’t post WordPress links to the Facebook page

I can't post links to my WordPress site on my Facebook business page. The URL does not contain any unusual or sensitive worlds (www.genesiskravmaga.com). When I try to post the link, there is no option for adding a thumbnail image and when submitted I get the "oops, something went wrong" message. I've seen this error reported elsewhere but have never seen a solution. Is it a Facebook problem or do I need to add some code to my site to allow Facebook to post the link?