how does subscription redirect work

I am troubleshooting an issue we are having with the subscription form when we add the widget to side nav. We have a complicated setup because we use a reverse proxy to go to a third party host so that our blog shows up under our e-commerce site’s domain.

This is what is happening…
Let’s say our blog home url is https://www.site.com/blog/
You are reading an post on url – https://www.site.com/blog/article1
When you enter your email and hit “subscribe” you post to
https://www.site.com/blog/article1
Then you get a 302 redirect to https://www.site.com/article1 which is a 404 b/c it is missing the folder name “blog”

What is causing this 302 redirect and how can I fix it to go to the correct url?

https://www.ads-software.com/plugins/jetpack/