Very dissapointing

I purchased a Hisense U989 on the 7th July 2017. On the 21st of November I removed my SIM card only to be blocked (I had not put a password on my phone) . I had no way of contacting Hisense as I couldn't get into my phone so my friend Deseree phoned on my behalf. She explained the situation and was told 'We will replace it'. We went all the way to your Jhb offices to see that they were CLOSED due to no water. We travelled from the Eastrand. The call center then advised we go to Teljoy Easy Fix in Midrand (more driving!) which we did. We were assisted and the gentleman picked up ANOTHER problem with handset. Being dual sim it was only reading 1 sim. He suggested the phone also be replaced. Today I get told that the motherboard needs to be replaced and they won't replace with new phone. This is unacceptable. The phone is 4 months old and it is a factory fault on phone! This needs to be addressed. I paid a lot of money for my phone. A VERY UNHAPPY CLIENT!