Microwave broken in just 4 months.

Hi. I bought a Hisense 37L microwave in January 2026. On 06 May 2026 it stop heating up my food. I sent Hisense my POP and detailed it's not heating up. I received a ticket number. It is now 18 May 2026, I have not received any communication either than the ticket number. I need to know how to proceed with the warranty because this microwave is only 4 months old!!.