Welcome to the Shopify Community! Happy to help. Another Shopify staff member just wrote a great, detailed post about what could be causing this error. In short, there are many factors that could cause this. Try following all the suggestions in Shipping issues - Community post.
Once you've been through all of the suggestions, the best next step is to reach out to our Support team directly so they can take a look at your account with you. This is a tricky error as it can be caused by different factors, sometimes it's best to have our Support team look over your settings with you and explain what is happening. While we’re not able to provide account-specific support via the Shopify Community at this time, we’d be happy to continue assisting you through live chat, email, or callback and get this error resolved!
Let us know how this goes! How is everything else going on your store? Are you following our general store setup checklist while you get started?
I went back this morning and added shipping rates for my home address. I'd ignored it because I don't do local deliveries. After setting up a rate for my home address it was successful. I'm a print on demand store that ships from the supplier so I'd not added the shipping rate. I just wanted to check back in and tell others who might be experiencing this problem.
Thanks for the reply, and for updating the post with the solution that's worked for you. Glad to hear you've been able to generate shipping rates.
Thanks for sharing a bit about your business as well. Can I ask which print on demand supplier you are using, or more importantly, are they integrated with your store? As in, can you assign inventory to this supplier within your admin, or do you contact the supplier outside of Shopify to fulfill orders?
If your third party supplier is connected directly to your store (for example, like Printful would be) you should not need to add shipping rates for your home location, since inventory shouldn't be assigned to your home location, but to the third party supplier, as you had initially thought. If this is the case, it's possible that your inventory is not assigned to the correct location, which is why your rates weren't displaying at checkout.
To check this, I recommend following our help document on assigning inventory to locations using the bulk editor. You can follow these steps to see if any inventory is assigned to your home location. If you're only selling from a third party supplier, you can change the inventory location to the supplier. Then, in your shipping rates, make sure you have rates available for Shipping from the supplier location (e.g. from Printful).
Let me know if you have any other questions! Thanks again for keeping us updated!