Can someone help me with this, other categories in our website are not showing when use our mobile phones to shop, though everything works fine when we use are pc.
This should be due to the theme you are using. Try to change theme to the default one and see if it works. Please do let me know if you need further assistance
Please share your store URL. Which category is hidden in mobile view? I assume, @charithrasanga is right, and that is your theme issue. But without seeing store, we can not tell for sure.