Why does my local delivery app give an error for certain addresses?

[JACLOGISTICS]

Hi I'm from South Africa and I'm using the local delivery Shopify app for close by areas, but when clients enter a delivery address the system gives an error message (this order can't be shipped to the address you entered.) I've added the maximum distance allowed on the local delivery shipping profile.

Shopify doesn't support Google autocomplete for South Africa which would make life so much easier, this makes it very difficult for myself and my clients as they need to message us about this error. Then I have to go into the back end of the website and create the order myself as the back end has Google autocomplete.