Bad costume service

I bought a laptop at russels thron tree soshanguve branch in May 2018 and December 2018 it shut down and never switched on then first week of January 2019 i took it back. When I returned the laptop it was said that they will call me and update me.A month passes without any update,I went to the store they said they can't assist me because the lady who took my laptop no longer works there and the manager is not around.So they took my number again and said they will give the manager my details when he is around,but he didn't.I called them several times and they keep on saying they will call me. Today I called the manager said he will call me,it's starting to frustrate me more because whenever I call they say they will check and update me and it's February already.