So you already have an EFI system partition on /dev/sda, but in the partitioning screen of the installer, you chose to create another one on /dev/sdb with the intention of using that one, but it still used the one in /dev/sda?
So you already have an EFI system partition on /dev/sda, but in the partitioning screen of the installer, you chose to create another one on /dev/sdb with the intention of using that one, but it still used the one in /dev/sda?