diff --git a/src/PubNub/CryptoModule.php b/src/PubNub/CryptoModule.php
index 47c71f96..b3b1c2e3 100644
--- a/src/PubNub/CryptoModule.php
+++ b/src/PubNub/CryptoModule.php
@@ -178,7 +178,7 @@ public function parseInput(string | object $input): string
             throw new PubNubResponseParsingException("Decryption error: message is not a string or object");
         }
 
-        if (strlen($input) == '') {
+        if (trim($input) == '') {
             throw new PubNubResponseParsingException("Decryption error: message is empty");
         }
         return $input;
diff --git a/src/PubNub/Endpoints/Access/GrantToken.php b/src/PubNub/Endpoints/Access/GrantToken.php
index fbe41a5e..80857651 100644
--- a/src/PubNub/Endpoints/Access/GrantToken.php
+++ b/src/PubNub/Endpoints/Access/GrantToken.php
@@ -246,7 +246,7 @@ public function sync(): string
 
     /**
      * @param string $token
-     * @return : string
+     * @return string
      */
     public function createResponse($response): string
     {
diff --git a/src/PubNub/Models/Consumer/FileSharing/PNGetFileDownloadURLResult.php b/src/PubNub/Models/Consumer/FileSharing/PNGetFileDownloadURLResult.php
index e13fa413..8620d8b2 100644
--- a/src/PubNub/Models/Consumer/FileSharing/PNGetFileDownloadURLResult.php
+++ b/src/PubNub/Models/Consumer/FileSharing/PNGetFileDownloadURLResult.php
@@ -13,7 +13,7 @@ public function __construct($result)
 
     public function __toString()
     {
-        return "Get file URL success with URL: %s" % $this->fileUrl;
+        return sprintf("Get file URL success with URL: %s", $this->fileUrl);
     }
 
     public function getFileUrl()