diff --git a/src/CachedKeySet.php b/src/CachedKeySet.php
index 76ef2ea9..6f867880 100644
--- a/src/CachedKeySet.php
+++ b/src/CachedKeySet.php
@@ -213,7 +213,7 @@ private function rateLimitExceeded(): bool
 
         $cacheItem = $this->cache->getItem($this->rateLimitCacheKey);
 
-        if (!$cacheItem->isHit() || !is_array($cacheItemData = $cacheItem->get())) {
+        if (!$cacheItem->isHit() || !\is_array($cacheItemData = $cacheItem->get())) {
             $cacheItemData = [
                 'callsPerMinute' => 0,
                 'expiry' => new \DateTime('+60 seconds', new \DateTimeZone('UTC')),