Mts — Slow internet Speed. Heat Up Device in 1-2 Hours and then not working

I have wifi postpaid dongle of mts MBLaze. Very Slow Internet speed. Bandwidth is 9 mbps. In speedtest.net only 30kbps speed. Page will take huge time to load. I have buy it before 1 week and it is started heat up. I have complained many time they say to reset it and asking for start for monitoring and then says everything okay they can not send people at home. Google ping is breaking and on his server ping is works fine without break. They said it is working fine because his own sites load okay and ping well.