poor customer service

Had a technician coming to my house to install my stove and didnt complete the installation, I then called Bosch customer service and spoke to Nomathemba whom i instructed that i do not want to have any interactions with the technician as he was very unprofessional but i wanted to pay him what was due to him, till today Nomathemba hasnt gotten back to me nor with the technicians banking details or invoice, meaning i dont even have proof that the stove was installed by a technician from Bosch