Help Help:Samsung Grand Neo i9060c issue


hi people, i'm new on this page and i'm finding for a solution of this problem. the problem is it, a friend gives me a phone (samsung grand neo i9060c) because my last phone been stolen, and he gives me that but the problem is that phone shows flickering, flashing and bugged images all the time, like a ubisoft game :v , well, i'm tried to reinstall the android by configuration and nothing's changed, i'm tried to enter to the download mode/ recovery mode / bootloader mode and nothing, i'm tried that by pc commands with adb and fastboot and the phone just restart, but the command by buttons doesn't works (the home button works when he want). But i've seen that the screen don't show any display problem when the phone says the start message of :Samsung Grand Neo, on the scren, he looks fine, and when i make the reinstall of android and it shows the character like dead or repairing, it looks fine again, i guess that problem is a error from the android build (in the config says 4.2.2 and says that phone is a GT-I9060L, but the sticker behind the battery says GT-I9060C). Help please. If they wish, i'll upload a video about this, showing the problem PD:sorry for my bad english i'm from Argentina.