Problem with HTTPS and internal request

I'm using Lua to detect request type and forward to one PHP server or another, but if I enable SSL, I'm getting an error (000 response).

Here is what I'm doing:

api.conf

    location /check-session {
        content_by_lua_file check-session.lua;
    }

check-session.lua

JSON = (loadfile "/usr/local/openresty/lualib/conf/utils/JSON.lua")()
local reqType = ngx.var.request_method
ngx.req.read_body()
if reqType == "POST" then
    local body = ngx.req.get_body_data()
    local decoded_body = JSON:decode(body)
    decoded_body ["meta"] = {
       //add some stuff
    }
    local modified_body = JSON:encode (decoded_body)
    local response = ngx.location.capture("/php",
        {
            body = modified_body,
            copy_all_vars = true
        }
    )
    for headerName, header in pairs(response.header) do
        ngx.header[headerName] = header
    end
    ngx.status = response.status
    ngx.say(response.body)
    ngx.exit(response.status)

php.conf

location /php {
    internal;
    root /api;
    fastcgi_param SCRIPT_FILENAME $document_root/ajax.php;
    fastcgi_param REQUEST_METHOD $request_method;
       fastcgi_param PATH_INFO $fastcgi_path_info;
       fastcgi_index ajax.php;
    fastcgi_pass php:9000;
    include fastcgi_params;
}

This worked fine until I started using SSL, Now I got a 000 response in logx and client will never see a response, just keeps loading.

Using openresty/1.11.2.1

Start by reviewing api.conf, check-session.lua, and php.conf, then reproduce the internal ngx.location.capture request with SSL enabled and compare it with the working non-SSL setup. Trace where the 000 response is produced and establish a response that reaches the client without hanging; the issue does not identify a failing test or expected fix.