Controller is firing but I can't get the $_GET

Here are the headers. Maybe you can see something obvious? BTW, when I send just the email, it seems to give me a status 200. So there is something wrong with the payload?
Request Headers:
POST /Subit_backend/register%7B%22lat%22:41.058304899999996,%22long%22:-74.0711244,%22email%22:%[email protected]%22%7D HTTP/1.1
Host: localhost
Connection: keep-alive
Content-Length: 74
Pragma: no-cache
Cache-Control: no-cache
Origin: chrome-extension://bdjgnodlhfmhghjhbkkkaaammfocdpib
X-Requested-With: xmlhttprequest
User-Agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/64.0.3282.186 Safari/537.36
Content-type: application/json
Accept: */*
Accept-Encoding: gzip, deflate, br
Accept-Language: en-US,en;q=0.9
Cookie: ciNav=no; XDEBUG_SESSION=PHPSTORM; cisession=t387m0rtvof1rmpoell1m3uakebg97l9

Request Payload:
{lat: 41.058304899999996, long: -74.0711244, email: "[email protected]"}
email
:
"[email protected]"
lat
:
41.058304899999996
long
:
-74.0711244

Response Headers:

HTTP/1.1 400 Bad Request
Date: Sun, 25 Mar 2018 22:03:59 GMT
Server: Apache/2.4.23 (Win32) OpenSSL/1.0.2h PHP/5.6.28
X-Powered-By: PHP/5.6.28
Content-Length: 1134
Connection: close
Content-Type: text/html; charset=UTF-8

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