Samsung — Problem in samsung e7

Address:

Mumbai City, Maharashtra

i bought samsung E7 two month back(i have bill and warranty), few days ago my screen's display got off automatically
but my phone was working and still working. i went to vijay sales(panvel), they told me i have to take my cell to service center . i took my phone to service center(vashi), they told me that your display is broken and it will cost 10000 rupees (my phone don't even have a single scratch) . i went twice there but without checking with machine they told me that it will cost 10, 000 .
i didn't submitted my phone(my phone is under warranty). that night my phone got started automatically
and was working properly but next day display got off again. Then one thing is confirmed that vashi service center don't know any thing.
i went to service center (kharghar) they told me that my phone don't have a
display problem but they don't have a machine to test . then i went to vijay sales they are telling meto again visit service center (vashi).