Don't be so angry, 慢慢教la, She only arrived in Hong Kong for 4 months and still need time to make adjustment. For my maid, she has worked in HK for 5 years but still has 蝦琭 thing ar.
My maid also very 硬頸. I think it is the characteristic of this race. But interpret it from another point of view, if she adopt your method, you can be assued that she will follow your instruction/ rule.
I find that I have scarified a lot on housework/ my rule because my maid really loves Timothy and Goh Goh. To me, it is the most important thing.