Xiaomi India — complaint regarding mi/xiaomi's bad services at service center

Address:

Arajibagh Azamgarh, Azamgarh, Uttar Pradesh

Hey there,
I am m. K. Malik owning a device redmi note 4. Recently i visited one of mi's service center at azamgarh up for replacement of display (It was cracked) and problem in power and volume buttons.
They submitted my device and give me a paper with written details about problems they will fix and signed with stamp on it.
Their paper says they will change display and fix power and volume buttons.
But when they returned (After 6 days), display was poorly assembled and buttons were not fixed.
Then i called them and they said we'll fix it, bring it back to us.
After reaching there, they treated me very badly and mannerlessly.

I said that i have proof that says you'll also fix power and volume buttons.
And they just said me we are not gonna fix it, do what you can.

Attachment : the paper with stamp they given me (Receipt).