Dual boot GRUB error "Version too old for 32bit boot"

I’ve been using Manjaro Linux & Windows 10 on my laptop using GRUB’s dual boot.
Yesterday I shrunk Windows 10 partition by 10 GB and installed another Manjaro Linux on that 10 GB.
(It was for testing & messing around dangerous configs)

It seems to have re-installed GRUB in the process since my original GRUB theme was gone.
GRUB menu showed 3 options: Newly installed Linux, Windows 10, and my original Manjaro Linux.

But when I tried to boot with my original Linux, it says "Version too old for 32bit boot"
and just returns to menu.
Windows 10 and newly installed Linux works just fine. All the files in the original Linux partition was fine, and when I typed ls -l in GRUB command line it showed all the partitions properly. What should I do?