Wa'alaikum assalam! Sayang, weight estimates at scans boleh vary quite a bit depending on the machine and the sonographer, even ±200-300g is normal lah. At 32 weeks, 1.9kg sounds within range, but honestly only your doctor can properly assess based on YOUR baby's growth curve and YOUR measurements. A few of us mum friends pun ada yang scan showed one weight, then baby came out completely different! Please check with your OB or midwife at your next appointment, they'll make sure baby's on track for you specifically. Don't worry too much yet, okay?