Game development consultation

https://www.xanje.com/ is my site. It is a browser-based virtual pet game. I need to hire a consultant to help me figure out how to stop its decline in player numbers over the past several years. We have been adding new content the entire time, advertising in multiple ways but nothing is working. We had an app for a few years, but nobody new joined through it. I need to hire someone who would be able to look at our site and our old app and know how to develop a new app for us and improve our game to where it stops declining.