I changed the company brand boot logo Lenovo Vibe K5 Plus and now don't start
The phone is probably a Mediatek device, Download SP Flash Tool, Install VCOM drivers and Flash it using a Windows Computer. I once did same thing for Tecno J5 and it ended up so. That's the thing you should do. But read how to flash it. Because flashing the preloader.bin file will brick it forever. So you must be cautious on the files you mark. Or ask me how if you feel fearful about the process. It will end up cool. Of it is still not MTK based, flashing stock ROM will unbrick it