Nginx 405 Not allowed when another site redirects to my Ionic app

I have an app that connects various payment gateways. When payment gateway navigates back to my site using url or I get a 405 not allowed from Nginx.

If I visit the page direct from my browser there is no problem also when I refresh the exact same page with the 405 error it loads perfectly fine.

It seems to be related to programmatic redirection to my site from payment gateway.

Details: Site is hosted in a AWS which redirects to http so Nginx doesn’t have to.