What if someone has not shaved pubic hairs for a long time
I have not shaved hairs on private parts this for a long time and is thus. Will all my prayers go in vain because I did not do this?
Try whatever means are available to you to do so now, without hurting yourself. Your prayers of the past would hopefully not go in vain, because you were not aware of the fact that you were doing something wrong. Even if you were deliberately refraining from cleaning yourself, acceptance of your prayers has got nothing to do with it directly. You will be a sinner for not shaving your hair and your prayers would be treated on the basis of their quality. However, it does happen that our sins do affect the quality of our prayers. One should, therefore, be careful about everything if one is concerned about the acceptance of prayers.