Swipe Elite — Screen has dots after it came from service center under warranty after 4 months

I purchased the phone on 18th July. After 5 months that's on January 2017 its battery got swollen & there were some more issues so I visited nearest service center that is ShreeRam service center in kalewadi, pune. The phone was under repair for 4 months, I got it back that too after so many calls & visits to service center & dealing with there arrogant attitude. Finally I get the phone back on 15th May with the phone having 4 big noticeable dots on screen which is horrible don't know what was happening from January to May at your service center. Also the service provider says that the battery charge 750 Rs it to be paid. I gave the phone back & filed other complaint for the dots that appear on screen. But I didn't receive any job sheet. Your server is not open nor do you people receive calls. whats the proof that i will get my phone back now that I don't have any job sheet.