This question is an exact duplicate of:
I have problem with my Raspberry Pi 3 b+. I think the SD card slot is broken.
I don't have a monitor, so I am using VNC viewer to remote my Noobs. I installed Noobs on my SD card, but when I plug it into my Raspberry Pi and scan the IP address (I've already make ssh &
wpa_supplicant.conf) the scanner cannot find the device. But then I tried to plug in my SD card into another Raspberry Pi 3 b+ (my friend's Raspberry Pi) the scanner finds the device.
Is it true that my Raspberry Pi's SD card slot is broken? Or can I find another way to fix it?