Hello,
Sorry for the inconvenience and for the screenshot.
On this our demo https://xstore.8theme.com/demos/2/eco-scooter/product/e-bike-ownership/ the product is simple so you can see quantity like this – http://prntscr.com/r5rup5 For variable products, like this one on your site http://prntscr.com/r5rv3g the fixed add to cart panel doesn’t contain the quantity form. There is “Buy now” button, and by click on it you will be scrolled to select variation form. It is not a bug, but predefined behavior.
Let us know if you need any other assistance.
To contact us by email you can use form on this page – https://www.8theme.com/contact-us/ but the forum is preferable way. Lightshot Screenshot tool https://app.prntscr.com/en/index.html makes screenshots and generates links of them then you can provide links of screenshots here.
Regards