diff --git a/src/Loaders/File.php b/src/Loaders/File.php
index e227b35..767a6fb 100644
--- a/src/Loaders/File.php
+++ b/src/Loaders/File.php
@@ -51,7 +51,7 @@ public function loadSchema(string $uri)
         if (isset($this->schemas[$uri])) {
             return $this->schemas[$uri];
         }
-        if (strpos($uri, $this->prefix) !== 0) {
+        if ($this->prefixLength !== 0 && strpos($uri, $this->prefix) !== 0) {
             return null;
         }
         $path = substr($uri, $this->prefixLength);