diff --git a/src/Traits/Cacheable.php b/src/Traits/Cacheable.php
index a0c232bd1e63ccb7ad0f4676000b0bf2ac3937f1..bf1058eef94bc82c5762d61664ad6958a8145f38 100644
--- a/src/Traits/Cacheable.php
+++ b/src/Traits/Cacheable.php
@@ -35,7 +35,7 @@ trait Cacheable
      * @param  int|null  $ttl
      * @return mixed
      */
-    public function fetch(int $ttl = null)
+    public function fetch(?int $ttl = null)
     {
         return Cache::remember($this->cacheKey(), $this->getTTL($ttl), function () {
             return $this->execute();
@@ -51,7 +51,7 @@ trait Cacheable
      * @param  int|null  $ttl
      * @return int
      */
-    private function getTTL(int $ttl = null): int
+    private function getTTL(?int $ttl = null): int
     {
         return intval($ttl ?? $this->ttl ?? config('redis-helpers.ttl'));
     }
diff --git a/tests/Assets/DateHash.php b/tests/Assets/DateHash.php
index 01f5a6d64eebeb19ff45fe9d2ebf5e8fa2397f25..fd297db1016a8f0c9a8afba8ad457c7fae5491c3 100644
--- a/tests/Assets/DateHash.php
+++ b/tests/Assets/DateHash.php
@@ -24,7 +24,7 @@ class DateHash
      * @param  string|null  $datetime
      * @param  string  $format
      */
-    public function __construct(string $datetime = null, string $format = 'Y-m-d')
+    public function __construct(?string $datetime = null, string $format = 'Y-m-d')
     {
         $this->format = $format;
         $this->date = date($this->format, strtotime($datetime ?? now()));