diff --git a/.gitignore b/.gitignore
index 1c203fb6..dfc291c3 100644
--- a/.gitignore
+++ b/.gitignore
@@ -55,6 +55,7 @@ clients/php/test/Model
 clients/php/test/Api/*
 !clients/php/test/Api/LocalesApiTest.php
 !clients/php/test/Api/UploadsApiTest.php
+!clients/php/test/Api/KeysApiTest.php
 
 clients/cli/cmd/api_*.go
 clients/cli/phrase-cli
diff --git a/clients/php/test/Api/KeysApiTest.php b/clients/php/test/Api/KeysApiTest.php
new file mode 100644
index 00000000..174717c9
--- /dev/null
+++ b/clients/php/test/Api/KeysApiTest.php
@@ -0,0 +1,218 @@
+<?php
+/**
+ * KeysApiTest
+ * PHP version 5
+ *
+ * @category Class
+ * @package  Phrase
+ * @author   OpenAPI Generator team
+ * @link     https://openapi-generator.tech
+ */
+
+/**
+ * Phrase Strings API Reference
+ *
+ * The version of the OpenAPI document: 2.0.0
+ * Contact: support@phrase.com
+ * Generated by: https://openapi-generator.tech
+ * OpenAPI Generator version: 7.0.1
+ */
+
+/**
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Please update the test case below to test the endpoint.
+ */
+
+namespace Phrase;
+
+use \Phrase\Configuration as Configuration;
+use \Phrase\ApiException;
+use \Phrase\ObjectSerializer;
+use PHPUnit\Framework\TestCase;
+
+use \Phrase\Api\KeysApi as Api;
+
+use GuzzleHttp\Client;
+use GuzzleHttp\Handler\MockHandler;
+use GuzzleHttp\HandlerStack;
+use GuzzleHttp\Middleware;
+use GuzzleHttp\Psr7\Response;
+
+/**
+ * KeysApiTest Class Doc Comment
+ *
+ * @category Class
+ * @package  Phrase
+ * @author   OpenAPI Generator team
+ * @link     https://openapi-generator.tech
+ */
+class KeysApiTest extends TestCase
+{
+    private $apiInstance;
+    private $mock;
+    private $history = [];
+
+    /**
+     * Setup before running any test cases
+     */
+    public static function setUpBeforeClass()
+    {
+    }
+
+    /**
+     * Setup before running each test case
+     */
+    public function setUp()
+    {
+        $this->mock = new MockHandler();
+        $history = Middleware::history($this->history);
+        $handlerStack = HandlerStack::create($this->mock);
+        $handlerStack->push($history);
+        $client = new Client(['handler' => $handlerStack]);
+
+        $config = Configuration::getDefaultConfiguration()->setApiKey('Authorization', 'YOUR_API_KEY');
+        $config = Configuration::getDefaultConfiguration()->setApiKeyPrefix('Authorization', 'token');
+
+        $this->apiInstance = new Api($client, $config);
+    }
+
+    /**
+     * Clean up after running each test case
+     */
+    public function tearDown()
+    {
+    }
+
+    /**
+     * Clean up after running all test cases
+     */
+    public static function tearDownAfterClass()
+    {
+    }
+
+    /**
+     * Test case for keyCreate
+     *
+     * Create a key.
+     *
+     */
+    public function testKeyCreate()
+    {
+    }
+
+    /**
+     * Test case for keyDelete
+     *
+     * Delete a key.
+     *
+     */
+    public function testKeyDelete()
+    {
+    }
+
+    /**
+     * Test case for keyShow
+     *
+     * Get a single key.
+     *
+     */
+    public function testKeyShow()
+    {
+        $this->mock->append(new Response(200, [], '{"id":"KEY_ID","name":"five","description":null,"name_hash":"NAME_HASH","plural":false,"tags":["upload-20231101_143051","fas"],"default_translation_content":"","created_at":"2023-11-01T14:31:01Z","updated_at":"2024-03-20T21:10:44Z","name_plural":null,"comments_count":0,"data_type":"string","max_characters_allowed":0,"screenshot_url":null,"unformatted":false,"xml_space_preserve":false,"original_file":null,"format_value_type":null,"localized_format_key":null,"localized_format_string":null,"custom_metadata":{"Name":"my name"},"creator":{"id":"CREATOR_ID","username":"username","name":"NAME","gravatar_uid":"UID"}}'));
+
+        $projectId = "project_id_example";
+        $id = "key_id";
+        $result = $this->apiInstance->keyShow($projectId, $id);
+
+        $this->assertNotNull($result);
+        $this->assertInstanceOf('\Phrase\Model\TranslationKeyDetails', $result);
+        $this->assertEquals('KEY_ID', $result->getId());
+        $this->assertEquals('five', $result->getName());
+        $this->assertEquals('my name', $result->getCustomMetadata()['Name']);
+
+        $lastRequest = $this->history[count($this->history)-1]['request'];
+        $this->assertEquals('GET', $lastRequest->getMethod());
+        $this->assertEquals('/v2/projects/'.$projectId.'/keys/'.$id, $lastRequest->getUri()->getPath());
+    }
+
+    /**
+     * Test case for keyUpdate
+     *
+     * Update a key.
+     *
+     */
+    public function testKeyUpdate()
+    {
+    }
+
+    /**
+     * Test case for keysDeleteCollection
+     *
+     * Delete collection of keys.
+     *
+     */
+    public function testKeysDeleteCollection()
+    {
+    }
+
+    /**
+     * Test case for keysExclude
+     *
+     * Exclude a locale on a collection of keys.
+     *
+     */
+    public function testKeysExclude()
+    {
+    }
+
+    /**
+     * Test case for keysInclude
+     *
+     * Include a locale on a collection of keys.
+     *
+     */
+    public function testKeysInclude()
+    {
+    }
+
+    /**
+     * Test case for keysList
+     *
+     * List keys.
+     *
+     */
+    public function testKeysList()
+    {
+    }
+
+    /**
+     * Test case for keysSearch
+     *
+     * Search keys.
+     *
+     */
+    public function testKeysSearch()
+    {
+    }
+
+    /**
+     * Test case for keysTag
+     *
+     * Add tags to collection of keys.
+     *
+     */
+    public function testKeysTag()
+    {
+    }
+
+    /**
+     * Test case for keysUntag
+     *
+     * Remove tags from collection of keys.
+     *
+     */
+    public function testKeysUntag()
+    {
+    }
+}
diff --git a/openapi-generator/templates/php/ObjectSerializer.mustache b/openapi-generator/templates/php/ObjectSerializer.mustache
index aa4f3302..8b8e1bd4 100644
--- a/openapi-generator/templates/php/ObjectSerializer.mustache
+++ b/openapi-generator/templates/php/ObjectSerializer.mustache
@@ -271,7 +271,7 @@ class ObjectSerializer
                 $values[] = self::deserialize($value, $subClass, null);
             }
             return $values;
-        } elseif ($class === 'object') {
+        } elseif ($class === 'object' || $class === 'array<string,string>') {
             settype($data, 'array');
             return $data;
         } elseif ($class === '\DateTime') {