diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 373be62..ded4e07 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -44,8 +44,9 @@ jobs:
 
     # Defines the WordPress and PHP Versions matrix to run tests on.
     strategy:
+      fail-fast: false
       matrix:
-        wp-versions: [ '6.6-RC3' ] #[ 'latest', '6.1.1' ]
+        wp-versions: [ 'latest' ] #[ 'latest', '6.1.1' ]
         php-versions: [ '7.4', '8.0', '8.1', '8.2', '8.3' ] #[ '7.4', '8.0', '8.1', '8.2' ]
 
     # Steps to install, configure and run tests
diff --git a/tests/wpunit/APITest.php b/tests/wpunit/APITest.php
index f14af87..dcc85ca 100644
--- a/tests/wpunit/APITest.php
+++ b/tests/wpunit/APITest.php
@@ -491,6 +491,20 @@ public function testRefreshTokenWithInvalidToken()
 		$this->assertEquals($result->get_error_code(), 'convertkit_api_error');
 	}
 
+	/**
+	 * Test that supplying no API credentials to the API class returns a WP_Error.
+	 *
+	 * @since   2.0.2
+	 */
+	public function testNoAPICredentials()
+	{
+		$api    = new ConvertKit_API_V4( $_ENV['CONVERTKIT_OAUTH_CLIENT_ID'], $_ENV['CONVERTKIT_OAUTH_REDIRECT_URI'] );
+		$result = $api->get_account();
+		$this->assertInstanceOf(WP_Error::class, $result);
+		$this->assertEquals($result->get_error_code(), $this->errorCode);
+		$this->assertEquals($result->get_error_message(), 'Authentication Failed');
+	}
+
 	/**
 	 * Test that supplying invalid API credentials to the API class returns a WP_Error.
 	 *
@@ -498,7 +512,7 @@ public function testRefreshTokenWithInvalidToken()
 	 */
 	public function testInvalidAPICredentials()
 	{
-		$api    = new ConvertKit_API_V4( $_ENV['CONVERTKIT_OAUTH_CLIENT_ID'], $_ENV['CONVERTKIT_OAUTH_REDIRECT_URI'] );
+		$api    = new ConvertKit_API_V4( $_ENV['CONVERTKIT_OAUTH_CLIENT_ID'], $_ENV['CONVERTKIT_OAUTH_REDIRECT_URI'], 'fakeAccessToken', 'fakeRefreshToken' );
 		$result = $api->get_account();
 		$this->assertInstanceOf(WP_Error::class, $result);
 		$this->assertEquals($result->get_error_code(), $this->errorCode);