Aww, sayang, tu memang common dengan baby baru, especially kalau kulit sensitif or ada reaction ke formula. Dupro boleh try, tapi memang sometimes baby's skin needs time to adjust, or mungkin dia prefer brand lain, a few of my mum friends pun kena tukar susu sebab baby derang develop rashes jugak. Best check dengan paediatrician dulu sebab they can identify if it's the formula, heat rash, atau eczema, then baru decide nak tukar ke formula lain macam Friso, S-26 Gold, or yang hypoallergenic types. Jangan tergesa-gesa tukar banyak kali dalam masa pendek, sebab baby's tummy needs time to settle, tapi definitely tanya doc, ok?