写给谁啊? Visa officer? Dear Sir/Mandam? Immigration Officer?
找到那个contact us网页了,
"If you contacted the National Customer Service Center with a case-related inquiry and more than 30 days have passed and you have not received a response"
还是需要等30天. 这30天估计还是指你没受到notice, 要不然还是90天了.