iPhone updates affecting this game

Hi,
I don’t have a iPhone, therefore I cannot guess what is wrong with this page.

Moreover, the website you mentioned seems to use an old version of the plugin (version 5.1.6): two bugs concerning Apple mobile devices have been fixed since this version (see https://github.com/yo35/rpb-chessboard/issues/128 and https://github.com/yo35/rpb-chessboard/issues/129). If these bugs correspond to what you encounter, I suggest you ask the administrators of https://new.uschess.org/ to upgrade RPB Chessboard on their website.

(please use the GitHub as much as possible instead of this forum for help requests, bug reports and feature requests: https://github.com/yo35/rpb-chessboard/issues)