I worked around it by posting manually. But thought y’all should be aware:
Threads: Error publishing post. 400, {"error":{"message":"The requested resource does not exist","type":"OAuthException","code":24,"error_subcode":4279009,"is_transient":false,"error_user_title":"Media Not Found","error_user_msg":"The media with id 18095041804546643 cannot be found.","fbtrace_id":"Abe10jn1q21HXQH1XOvlvna"}}