There can be several reasons for this. On the one hand, something may have broken during installation, which is usually directly visible, such as broken contacts or a dented display. Or perhaps something else is defective on the mobile phone apart from the display. On the other hand, it can happen that a display arrives broken despite being tested during shipping. If all the original guarantee stickers are still on the display, you can return it in this case. Please understand that we do not take back displays with torn-off guarantee stickers.