Sony India — about money fraud by a army soldier

Sir i see a advertising on olx so i interested in mobile redmi note 5 pro.
A manjeet singh named person give his phone no. And asked about payment.
He say that u will pay half money first and another after delivery
I am payed 5000 for this phone
By paytm
After 3 hours he say that"u pay full amount for this phone otherwise we not dispath the courior.
I[censored] not done i will refund"
He is not refund my money i belive on army dress so i am payed
After this i hate indian army
Please help me i am a student.
He say he is from freozpur cantt.

Fraud by a person in his name manjeet