Chosen Solution
I left my phone to charge l. When I gt back I noticed some weird black horizontal lines at the bottom of my screen. I restarted my phone but the result is still the same.the more I use the more the lines appear
You probably have a damaged screen. That is the most logical thing to change first unless there is something else that happened recently to your phone like water damage or a hard fall. You can order a replacement screen from iFixit. Follow this guide to install it.
