Parameter Missing or Invalid: Required parameter missing or invalid: items

[Daniel3316]

Hello community,

Since last Monday I keep recieving the error 'Parameter Missing or Invalid: Required parameter missing or invalid: items' when trying to add a product to the cart. 

Also the 'add to cart' button turns grey (inactive) when I select a variant within the product page. 

I'm using Dawn theme version 6.0.2. Is there anyone who has had the same issue?

Thanks in advance!