iPhone service issues

[drdang]

The upper half of my iPhone 6 Plus screen has been clicking very loudly for a month now, and last week I discovered a vertical line on the right edge of the screen. It would only be visible on certain light colours but it certainly is there. So finally I took the phone in to the nearest authorised service centre (India, no Apple Stores) and their response was that the small dent on the corner of my phone was probably the cause of the loose screen. I had bumped the corner when it was pretty new and was using one of those cases where the top is uncovered. Then they brought out a pretty rough iPhone they had in the centre and showed me that it had the vertical line too so it was normal. They said they would tighten the screws to make the click go away but it was a "cosmetic issue because of the dent" and I shouldn't bother if it comes back. It came back that night. So my question to you guys is, should I be satisfied with this or was I duped?