Shipping Rates are not adding up

[Enzie]

I am using a drop shipper and have added rates based on weight. When I check out with product A I get the correct shipping rate. Same goes for product B. However when I add both A and B to the cart I get "Your cart has been updated and the items you added can’t be shipped to your address. Remove the items to complete your order."

I can not figure out where the problem is since individual both products show the correct shipping rate when they are added separately. 

Link to the products  A - https://portraits-by-nc.com/products/rusty-vintage-style-standing-bird-bath-pick-12-scale-dollhouse-...

@Matt_Goodwin 

B - https://portraits-by-nc.com/products/rustic-vintage-looking-birdhouse-pick-1-12-scale-miniature-doll...

Please help.