I would think that *maybe* you have the seat installed incorrectly. I know the seat you have & would think it should fit better then it sounds. I would suggest taking it to be fitted by someone who does it regularly but I also wonder if maybe you have it reclined too far?
We did tilt it more upright, but stood back and both agreed it was far too 'upright' for a newborn. I am hoping when we get it checked they can fix it to a better position