diff --git a/api.lua b/api.lua
index 230d397..b44b3ae 100644
--- a/api.lua
+++ b/api.lua
@@ -229,7 +229,7 @@ function Panel:update(def, txt_elems, img_elems)
         self.hud_text.bg_hud_txt = v
         self.background_def.text = v
 
-        if self.is_visible then
+        if self:is_visible() then
           player:hud_change(self.hud_id.bg_hud_id, "text", v)
         end
 
@@ -239,7 +239,7 @@ function Panel:update(def, txt_elems, img_elems)
         if k == "title" then
           self.hud_text.text_hud_txt = v
           self.title_def.text = v
-          if self.is_visible then
+          if self:is_visible() then
             player:hud_change(self.hud_id.text_hud_id, "text", v)
           end
         else