macbook replacement

Apple repairs come with a modest warranty of their own. If you paid for this same problem less than 90 days ago, return to the place of service and ask them to "make it right".

They are not likely to replace it outright at this stage.

You need to explain with more detail - depending on the damage (what exactly is damaged???), and if you are under warranty (or purchased Applecare +), Apple will repair it. Only after several repair attempts would they maybe consider a replacement.