[ForceHSS]

If you have not talked to your host yet I would if this has only happened maybe they changed something if they have not I am sure they will know how to fix if not give them this

server { 
    listen 80; 
    client_max_body_size 4G; 
  
    access_log /var/sites/webapp/logs/access.maintenance.log; 
    error_log /var/sites/webapp/logs/error.maintenance.log info; 
  
    server_name api.webapp.com; 
  
    # this guy redirects any path to /api.json 
    rewrite ^.*$ /api.json last; 
  
    location / { 
        root /var/sites/webapp/webapp/; 
        index api.json /api.json; 
  
        # this is the magic 
        error_page 405 = $uri; 
    } 
  
}