[iOS app] xmlrpc 403 error

I’m trying to set up my iPad to have the ability to post to my self-hosted site at a-museproject.com but i keep getting an error saying “Unable to read the WordPress site at that URL.” After digging around the FAQ and online, I tried to check the xmlrpc link from my site (https://a-museproject.com/xmlrpc.php) but end up with a 403 error. How can I overcome this issue?