One Plus - Phone not replaced

i bought new one plus *t phone from reliance digital, after * days it start heating up without any use , i complainted to reliance digital and they said we did not do anything , after that i went to one plus service center personally and show them how it was heating with normal use, but they were not agreed to understand but there were also * customers sit there they also agreed that phone is heating but in service center engineer not want to understand i did everything what they asked to me to do that , i did for *.** hours continuously but they not want to understand my problem , they said they did software after * days and problem is solved but it is not solve yet , i told to reliance digital CRM to solve my problem he said u do what you can do ill not do this