How can my friend change her address at Immigration if she is living with us temporarily in Thailand?

... Can anyone help please? Our rental contract expires end December (and then we move out). We have a younger friend, she is a teacher with a non-b visa and has work permit for her school not far from our home in Jomtien; her rental contract at her Condo expired last week. She moved in with us (in our house) yesterday and will stay for ±2.5 months. In this period she will visit her home country for one month and I offered her to live with us until she returns from vacation and then she will find new accommodation. She now needs to change her address at Immigration to obtain a new white slip (Receipt of Notification) for her passport, but our landlord says she is not part of our rental agreement so they cannot do it for her. We are all South Africans. What do we do? Any advice will help. Thank you in advance -Linda.