diff --git a/lib/pleroma/web/activity_pub/activity_pub_controller.ex b/lib/pleroma/web/activity_pub/activity_pub_controller.ex
index 17c3ca638..edbcb938a 100644
--- a/lib/pleroma/web/activity_pub/activity_pub_controller.ex
+++ b/lib/pleroma/web/activity_pub/activity_pub_controller.ex
@@ -35,7 +35,7 @@ def inbox(%{assigns: %{valid_signature: true}} = conn, params) do
 
   def inbox(conn, params) do
     headers = Enum.into(conn.req_headers, %{})
-    if !(String.contains(headers["signature"] || "", params["actor"])) do
+    if !(String.contains?(headers["signature"] || "", params["actor"])) do
       Logger.info("Signature not from author, relayed message, ignoring.")
     else
       Logger.info("Signature error.")