diff --git a/src/Oidc/Authentication/TokenAuthentication.php b/src/Oidc/Authentication/TokenAuthentication.php
index cdc4cbb..ac689a0 100644
--- a/src/Oidc/Authentication/TokenAuthentication.php
+++ b/src/Oidc/Authentication/TokenAuthentication.php
@@ -60,7 +60,7 @@ class TokenAuthentication extends Authentication
 		if ($this->token->isExpired() && isset($this->refresh_callback))
 		{
 			$callback = $this->refresh_callback;
-			$this->token = $callback($this);
+			$this->token = $callback($this->token);
 		}
 		return $request->withHeader('Authorization', 'Bearer '.$this->token->getAccessToken());
 	}
diff --git a/src/Oidc/Flows/ServiceAccountFlow.php b/src/Oidc/Flows/ServiceAccountFlow.php
index fdeab19..48b3dc7 100644
--- a/src/Oidc/Flows/ServiceAccountFlow.php
+++ b/src/Oidc/Flows/ServiceAccountFlow.php
@@ -35,6 +35,6 @@ class ServiceAccountFlow
 	 */
 	public function getServiceAccountToken(): Token
 	{
-		return $this->client->createTokenFromClient();
+		$token = $this->client->createTokenFromClient();
 	}
 }