Fatal error: Invalid template - php

Question

i am new to PHP and it seems i ran into some deathcode.
Error given:
( ! ) Fatal error: Invalid template: FPage in /home/jharvard/vhosts/localhost/includes/functions.php on line 218
Call Stack
# Time Memory Function Location
1 0.0001 124636 {main}( ) ../buy.php:0
2 1.3034 144340 render( ) ../buy.php:6
3 1.3035 144476 trigger_error ( ) ../functions.php:218
This is as soon as i POST to my form at Buy.php
<?php
require("../includes/config.php");
if ($_SERVER["REQUEST_METHOD"] == "POST"){
$symbol = $_POST["symbol"];
$price = lookup($symbol)["price"];
render("FPage", ["price" => $price]);
}
else{render("BuyPage.php");}
?>
BuyPage and FPage are respectively:
<form action="buy.php" method='post'><input name="symbol"><input name="SAmount"><input type="submit"></form>
and
<?php
echo $price;
?>
And functions.php(If need be) is at http://pastebin.com/Kd9Zg32S
What i was going for:
Pretty much a simple program to "buy" fake stocks for a programming challange. Lookup pretty much looks up a stock's symbol on yahoo finance and returns a list.
Render pretty much renders the template along with header and footer as well as extracting and inputting any variables passed in.
However about half way around the place i get struck here with a "hairball" of bugs, and this one i just cant seem to pass by.
Debugging help is highly appreciated.
Ps: Config is just a file that checks if the user is logged in, loading in functions e.t.c e.t.c, i brought in all the code that i thought was needed, if more is needed please notify me.

Answer 1

...
render("FPage", ["price" => $price]);
}
else{render("BuyPage.php");}
...
You render "FPage" and "BuyPage.php"
"BuyPage.php" works but FPage does not.
Try replacing "FPage" by "FPage.php".