How can one get rid of demonic possession, and what is the expiation for sacrificing and seeking help from charlatans?

The treatment for touch (mass) is through Ruqyah Shariah (Islamic exorcism). As for sacrificing to the jinn قرين (companion jinn) or other creatures, it is forbidden and considered shirk (associating partners with Allah). Sacrifices to thejinn have been prohibited. It is not permissible to seek healing through forbidden means, because Allah has not placed healing in them. Furthermore, seeking healing through shirk and disbelief is forbidden by the consensus of scholars.