welcome! You haven't said if you're someone who works on this website (and therefore have access to the admin area) or a customer. If it's the latter, your best bet is to contact Plant Guru and report the problem to them.
If you do have administrative access, you'll most likely find the problem is in the configuration. Perhaps there are no shipping methods set up that cover the delivery address in question, or maybe the weight and/or value of the items in your cart isn't covered by the available shipping methods.
Without seeing how the shipping methods are set up I don't think I can offer anything specific though.