Shopify doubles the shipping price when a customer order from more than one supplier

[Tyrannax]

I manage a print on demand store that utilizes multiple POD supplies (printful, prinitify, etc.) and weight-based shipping. However, when a customer orders a product from each supplier, Shopify doubles the price of the shipping rather than adhering to the shipping rules I've established.

For example, a shirt is 0.1lbs (printful) and a mug is also 0.1lbs. (printify). I have 0.1lb items set to $4.00 shipping and 0.2lb items set to $6.00. So, if a customer orders both a shirt and a mug, the shipping should be $6.00. However, Shopify ignores my shipping rules and simply doubles the price to $8.00. It does this because the locations are different (printful and printify), but shipping rules should absolutely take priority over this. It's quite a frustrating issue that I'm sure hasn't been solved, but I'm hoping someone has come up with a solution by now. 

I want to note that I don't want to use a free shipping model, and I don't feel as though a paid app should be necessary for what should be a basic feature.

Thanks in advance for any help on this matter!

[JoesIdeas]

I had a similar problem and reached out to Shopify support. They told me it's a switchable feature but you have to request from them.

For example, by default multiple locations will incur multiple ship charges.

I would reach out to them, explain your situation, and ask them to charge shipping as a whole instead of individual items / locations. I think that will solve your problem.