升级后的RAM未显示

我得到了Lenovo IdeaPad S145,可用于大学。但是,它仅随附4GB的内存,因此我决定再安装8GB(DDR4-2666 SODIMM)以提高性能。我确实在网上检查过,但RAM似乎兼容

I have now installed the ram, but it is not showing up when I look in the terminal as well as when I look in the BIOS. Here is the picture from the terminal. I have also wiped the drive and completely reinstalled Ubuntu 20.04 which did not help either.

任何帮助将非常感激!