Issues with Shipping RATE

Hi There,
We’re having issues with Shipping Rate, it’s weird that sometimes working sometimes it doesn’t. The way we have shipping set up here is Region and weight class (not weight based, just four classes).
See below summary for the issues:
1. Yes can be updated but some regions doesn’t display the right value like in “South Australia” for example. (now it’s working)
2. If you have multiple items, the highest value of the shipping price is only displayed, not summing up.
3. Tested when paying, shipping price is displayed, which is good…. (but not all Regions like South Australia which has same value set up for Shipping Rate)

I’ve already submitted ticket but until now it’s so slow and didn’t receive response yet, so frustrating.

Thanks