Need to keep bugging them.

Use all three
1. Email complaint form
2. Live agent chat in pos website
3. Call (hard to get)

I did this and 50% of the time I'd get an agent that can help move things along. Longest I have to wait is 1 week and I usually buy from sellers in selangor/KL even though I'm based in another state for now.
Yeah happened to my friend

He is in subang and bought an item from a puchong seller but item went to KL and is stuck there for some reason
Need to bug them
Use the three channels I mentioned above.