Sony Spresense built-in app not found

I tried the examples/hello of the Presence SDK tutorial according to the instructions in the tutorial.As shown in Figure 3 of 1.4. Loading Images to the Spresense Main Board, the load was successful and the display up to reboot (size is 154176 bytes, slightly different from the display in Figure 3), and the display also shows updater#sync.

However, if you connect with minicom and type hello, it becomes command not found, and if you look at it with help, there is no entry in Builtin Apps:.The Nuttx version is 7.22.

Also, in the tutorial, the examples directory was written to be under sdk, but
The download was in the same hierarchy as sdk (so I did mv).

$git clone --recursive https://github.com/sonydevworld/spresense.git

For some reason, the spresense directory did not appear until I downloaded it twice.

What should I do? Please let me know.