There is something wrong with family education.
There are problems with the fruit, mostly because of the roots. Children's lack of gratitude is often a problem of family education.
Chinese parents
Parents in China tend to focus on their children and pay too much for them. They are used to arranging their children's trifles, but forget that children have the right to learn to love and pay.
Love is too strong
Your love is too strong, but you missed the opportunity to let your children learn to be grateful. The more parents pay, the easier it is to encourage children to feel unworthy, and often they can't raise grateful children.
Children are superior.
Parents have given everything, but they have bred their children's sense of superiority. Children are used to their parents' efforts, but they don't know how to be grateful and enjoy their parents' efforts with peace of mind.
Children should learn to be grateful.
Many parents tell their children, "You just have to study hard and we'll do the rest." After a long time, children feel that their parents should pay, but they don't feel the difficulty of the adult world.