Quite desperate here - since today (as far as I know) I can't put any products into the cart. It just shows no reaction (No error message).
The link is : www.mila-and-mike.com
I just tested your site on my laptop and over my phone. From here all is working fine ;).
Try on other devices and see if the error is only on your devices. From there is the error is still presenting feel free to contact me over DM or email me at email@example.com. I would gladly help you more on this.