diff --git a/app/views/games/picture_display.json.jbuilder b/app/views/games/picture_display.json.jbuilder
index 4c806d142..eb2309f9b 100644
--- a/app/views/games/picture_display.json.jbuilder
+++ b/app/views/games/picture_display.json.jbuilder
@@ -21,7 +21,7 @@ if @type == "image"
 elsif @type == "html"
   json.iframe_src File.read("#{@user_path}/#{@user_picture[0]}")&.html_safe
 elsif @type == "txt"
-  json.contents @contents
+  json.contents @contents.to_s
 elsif @type =="qrcode"
   json.qrcode_str @qrcode_str
 elsif @type == "mp3" || @type == "mp4"