Poor service and bad product from Hisense

I bought a Hisense gas hob at Makro and it has only been in use for about a week and the stove makes an orange flame instead of a blue flame. I contacted Hisense to send a technician to check and they claimed that the installer used the wrong jets so I must go back to the installer. The installer confirmed using the correct jets but Hisense still refuse to send a technician to come check the issue with the stove. I logged the call a week ago and still no joy from hisense.