thanks. 我是新手mother and so silly to buy different brand 奶樽, both pigeon and NUK. Later I found that I should buy one brand otherwise baby is not adequent to different shape of teat. After searching in bk, I found that I can replace pigeon teat with NUK teat to solve the problem.
One more question to ask, I found there is a 破口 (not a hole, with 0.5cm) in the 氣孔 of the yellow teat (but only a hole for the transparent one), is it normal or the rubber has been 老化? Actually the 奶樽 is new and I bought it in Jusco bb fair (February??) but I just discover it because I want to clean it now.