Aiyah, 21 months is such a tricky age kan, a few of us mums went through the same phase, it's so stressful! One thing that helped is we stopped forcing, and instead just keep offering the same foods without pressure, because sometimes they need to see it many times before they'll try. My friend swears by letting her toddler feed herself with hands or a spoon, because suddenly it becomes a game instead of rejection, and she also makes sure not to have too many snacks in between meals so dia betul-betul hungry at mealtimes.