Helper always giving black face

I have a filipino helper who had been with us for a year. When we engaged her, she had 10 years of working experience in Singapore, mainly working for expats caring for their children (2years and above). She had never cared for infant. She is able to converse very well in english. During our interviews with her we already told her her main job scope is to help look after our newborn (was pregnant with 2nd child at that time). She said she is ok to try caring for infant though she had not done that before. Generally she is still ok in her work, though nt very detailed. She is ok with the children. But the problem I have with her is she gives us attitude very easily, and alot of times makes me feel that I have to see her face instead of her seeing mine. A little bit of correction in a kind way result in her giving black face. End up it is really difficult to correct her or tell her my preference without dealing with her black face for the whole day. Giving her adhoc task such as looking after my 2 children while I go out (so far I only only did it twice and I stop because I am really scared of her black face now) also result in black face. Her daily chores is just general household chores and taking care of my youngest, nw 8mths old, while we are at work during weekdays. Her work starts at 6.30am, end off between 7.30-8pm. She breaks between 9-10am, 12-3pm, 5-5.30pm, although sometimes this may be compromised if my baby do not want to sleep. We gave her a room of her own, she do not need to do night duty, gave her wifi, no phone curfew, no cctv, include her in our decision making as we want to respect her opinions, treat her like our own family members. She gets off day every Sunday, and she basically goes out from 7am-9pm and allowed her to do so. We try to treat her with as much welfare and respect as possible, but due to the frequent black face, I really feel she does not appreciate our kindness at all. This upsets me alot and do not think we deserve that every little black face. I get that it is very tiring to tc of baby, but we alrdy try to lesson or balance her workload as much as possible in my opinion. Also, after all these are also her duties, duties of most helpers with young families, and the very reason we engaged her. We also took over all child caring duties the moment we reach home at 7pm. She does not need to tc of my eldest (4yo) at all as well. We go out every sat afternoon without her (she herself does not want to follow us) from 3-8pm and she basically did nothing at home and when we are back, she just need to wash 2 milk bottles and she can go back to her room and call it a day. So in actual fact, she only work half from 6.30am-12pm on saturday (12-3pm is her lunch time break), even though her pay includes Saturday as her work day. I did not even say anything. By treating her as well as I could, I do not expect her to go the extra mile, but at least dont give me black face as and when she likes even when I talk to her nicely? I thought engaging a helper would allow me to relieve alot of chores and to have me time even at home, but she makes me feel like I am not allowed to do so. I really dont get if general household chores and taking care of baby, cooking dinner is really very heavy load? If you can elightened me, pls do.