Hello,
I just tried to make an account with one Iphone and macbook and it worked. If you want more help, send me a PM.
Cheers,
I also tried your site on my iPhone, but it looks like the site is not mobile-friendly. The site looks like don't have a mobile version because still, we see the desktop screen in mobile as well. If that is true, then it is not so convenient to play from mobile. You need to make mobile site friendly then it will be good to play on mobiles. It is just based on my experience.
Bitsler is mobile friendly at least for me as android user, probably you need to use other browsers on your iPhone. Have you tried it? As my experience, when I use opera browser and puffin browser in my android then it will be in desktop version but if I use chrome then it will be mobile version.
So I guess the main problem here is about the browser you use.