How can I change the default shipping location in my dropshipping app?

[Doktor1980]

Iam doing dropshipping through 3rd party app. All inventory is there.  My business address doesn't have inventory.  My business address is listed as default location and I cannot change it. So when clients make an order through my website, shipping charges get calculated based on the location of my business address (as if i was shipping the order from there) not the 3rd party app address,  from where orders are actually shipped.  How do I change that?  Thanks

[Doktor1980]

Thanks for response.  I don't mind. I could use some help. Iam listening.