Backseats not comfortable,caused neckpain and backpain

Width of backseats is little short,and the angle of them is almost 90 degrees, so my family complained neck and back pain when we travelled around 50 kilometers. I ran it around 500 kilometers, mileage given is poor around 12.5 km per litre, and navigation maps sucks, it shows roads allowed where in actually turning not allowed,once it has given me route of 42 kilometers whereas actual distance was 25 kilometers.