Xiaomi India — Xiaomi Service Center returning Phone in Damaged condition

Address: Mumbai City, Maharashtra

Submitted my Mi3 phone to New Tech Solutions Vashi for Phones Touchscreen issue and Proximity Sensor, The Phone was repaired and o one bothered to inform for collection, Upon visiting to service centre and when the phone was given for testing the phone was found damaged at the bottom, and when informed to assistants they blamed me of submitting damaged phone, but the service sheet had all cleared, the manager was ready to replace the damaged part but no word from their end and their phone numbers are not working at all, Please help me to get out of this pathetic support