How come my request returns Invalid_Api_Key? Simple HTTPS

local HttpService = game:GetService("HttpService")
local url = "https://fortnite-public-api.theapinetwork.com/prod09/upcoming/get"
local api = {['Key']="5515aff128c1280bc37c6080265619bd"}
local response = HttpService:GetAsync(url,false,api)
 

local data = HttpService:JSONDecode(response)
for _,v in pairs(data) do
	print (v)
end

Its attempting to decode the 'url' and parse it.

The API Key is brand new, and i've tried this using multiple keys, none working.

Looking at the documentation, the API is expecting you to make a POST request with the Authorization token as a header. You're attempting to make a GET request with some "Key" header.

local authHeader = "Authorization: yourAPIKey"
local response = HttpService:PostAsync(url, "", Enum.HttpContentType.ApplicationJson, false, authHeader)

Also, don't post your API keys into the public. And next time when posting a question about a less-known third-party-service, please provide a link to the service and its documentation.