Light down-filled jacket

Light down-filled jacket, the manufacturer indicated size 44, but in our measurements, it's size 38/40. The jacket has recently been dry cleaned. The length of the jacket is 66cm. Measured without the collar part. The collar is foldable. Under the armpits 49cm x2, Waist 45cm x2, Bottom part 54cm x2. It won't be suitable for very cold winter.