diff --git a/src/Valkyrja/Crypt/SodiumCrypt.php b/src/Valkyrja/Crypt/SodiumCrypt.php
index <HASH>..<HASH> 100644
--- a/src/Valkyrja/Crypt/SodiumCrypt.php
+++ b/src/Valkyrja/Crypt/SodiumCrypt.php
@@ -246,7 +246,7 @@ class SodiumCrypt implements Crypt
      */
     protected function validateDecodedStrLen($decoded): void
     {
-        if ($this->isValidDecodedStrLen($decoded)) {
+        if (! $this->isValidDecodedStrLen($decoded)) {
             throw new CryptException('The message was truncated');
         }
     }
@@ -298,7 +298,7 @@ class SodiumCrypt implements Crypt
      */
     protected function validatePlainDecoded($plain): void
     {
-        if ($this->isValidPlainDecoded($plain)) {
+        if (! $this->isValidPlainDecoded($plain)) {
             throw new CryptException('The message was tampered with in transit');
         }
     }
Fixing invalid checks to throw exceptions.