Thanks for the solution. The issue have been solved. It caused by the plugin I used to combine the cart page and checkout page together. The function called “Enable single page checkout” in the plugin called “Direct checkout, WooCommerce Single page checkout , WooCommerce One page checkout”.
After disable the “Enable single page checkout” function, and the problem solved. One of the coupon doesn’t work at mobile devices, because I didn’t publish the cart page on my site. (I still don’t know why it works on computer site). After pubishing the cart page. All my issues mentioned above have been solves. Thanks for all you help and have a nice day!