this causes the problem?
- happens after ram memory and hdd change
- becomes from modem encryption and dns settings
- happens from hdd formatting
- It happens from the slowness of the internet.
is important: first of all check if your device has internet recovery support and search.
1- Make sure you have a working Internet connection. internet service is a must.
2- If possible, try the installation with an ethernet cable.
Change the 3-modem wireless encryption type to WPA wpa2. give dns if necessary.
4- You can do mac recovery in 3 ways. in this video he explained 3 shapes separately. The first operating system, the last installed operating system, the latest operating system, 3 of them are explained in the video, how to log in with individual keys. Try all 3 of them.
5- Prepare and install the mac os installation usb with an external usb memory.
you can watch this video.
6- Make sure the time and date are correct.
See this video to fix the time and date.
7 – Finally, install the hdd on a different mac pc and insert it into your own hdd. if you can.