A person is in hell because they chose to be there.
The Christian responsibilty is to tell everyone what we know, that hell is real but they do not have to go there, the price has been paid, or they have to do is accept the free gift of salvation (Rom.6:23)
If they do not accept the gift, then they will stand before the Great White Throne Judgement on their own merits which means eternal damnation (Rev.20, Isa.64:6)
Therefore a person is in heaven because they chose to be there.