Welcome to the expectation of teachers in Taiwan!
You’re supposed to educate every child perfectly and also be a therapist to every child’s parent. Standard practice.
I recommend setting up office hours. “I teach children lessons, also known as ‘my job’, from x time to y time and will be available at z. Do not call me before 8 am or after 9 pm because basic human decency dictates that you respect my rest/sleeping hours”
Edit: also, put your phone on “do not disturb” to start from the exact minute you said your “do not call me” time was, that way you don’t even need to see the calls coming in and parents who call twenty times are not bothering you. Same for email/messages. Do not open them or reply during your designated rest time. If parents complain to the admin, tell them to eff off and find a new job