Frayed cable inside front derailleur
If you are still in your warranty period bring it in to the dealer your bought the bike from and ask them to replace the cable. It is unlikely that anything you have done in normal use would have caused this. At this point it is a relatively easy fix. I have worked on shifters where the cable has been used breaking a single strand at a time until complete failure. It left a birds nest of cable ends that wouldn't pull out in either direction. If they aren't willing to fix it under warranty still have it repaired.