MarketPress add to cart not working

I've moved a site from http to https and then MarketPress add to cart feature stopped working. Adding a product to the cart gets stuck at the animation.

Browser console show this error: Mixed Content:
The page at 'https://mydomain.com/store/products/category/audio/' was loaded over HTTPS, but requested an insecure XMLHttpRequest endpoint 'http://mydomain.com/wp-admin/admin-ajax.php?action=mp_update_cart'. This request has been blocked; the content must be served over HTTPS.

Did a search and replace from the database, but it didn't fix it.