diff --git a/js/mm_client.js b/js/mm_client.js
index a1a4200..adfb277 100644
--- a/js/mm_client.js
+++ b/js/mm_client.js
@@ -81,7 +81,7 @@ class MattermostClient {
 			throw Error("Already logged in on this server");
 		}
 
-		const response = await this.post("/users/login", undefined, {login_id, password});
+		const response = await this.post("/users/login", {login_id, password});
 		const token = response.getResponseHeader("Token");
 		if (!token) {
 			throw Error("No Token header in response to log in request");