try adding chan to preimage update

Author: joostjager

lightning/src/ln/channel.rs

@@ -7277,7 +7277,7 @@ where
 				payment_info,
 			}],
 			channel_id: Some(self.context.channel_id()),
-			encoded_channel: None,
+			encoded_channel: Some(self.encode()),
 		};
 
 		if !self.context.channel_state.can_generate_new_commitment() {