Microsoft — Engineers intentionally made my handset faulty

Address:

Kolkata, West Bengal, 700001

With an expectation, I have visited Nokia/microsoft service centre of Lenin Sarani, Kolkata to repair my Lumia 535 set's touch screen as it was broken falling from my hand. They have charged 1990 INR to replace the touch pad and have returned back to me. From that day, touch screen was not responding properly. After 2 months, when I was thinking to buy a new handset, again touch screen of my handset has broken. Being quite upset, have gone to a local mobile repairing centre and they have done a miracle job. They have only taken 400 INR from me and gave me my phone with a new touch pad, even sensing problem has been disappeared.
Are the engineers of your service centres really well trained or do they just intentionally to make customers dupe?