Value of mashsb_jsonshares shows error

I’ve got Mashshare set up with Sharedcount. I entered my API key into the Mashshare plugin and added my domain to the whitelist. However, one of my posts keeps showing this error in the custom field mashsb_jsonshares:

{"Error":"The domain of the queried URL is not on the authorized whitelist of this API key.","Type":"invalid_queried_hostname","HTTP_Code":401,"Twitter":0,"https":{"Error":"The domain of the queried URL is not on the authorized whitelist of this API key.","Type":"invalid_queried_hostname","HTTP_Code":401},"total":0}

It seems like my other posts/pages are working and updating fine. They are all on the same whitelisted domain. Does anyone know why this one won’t work?