it is against the labor law if you :
1. don't let her have 1 rest day every week (that is, 4 rest days a month); AND
2. don't 補水 (about $110 per day) for the rest days she worked
is better for you to 補水 for the days she worked, and from now stick to the labor regulations, or else, your maid may bring you trouble if she sues you