Can't install custom recovery (TWRP)

Hello,

I have a big problem with my H815.

My H815 bootloader is been unlocked.

II try to install TWRP, but without success:

Code:

---

C:\Users\~\Downloads\G4\platform-tools>adb reboot bootloader

C:\Users\~\Downloads\G4\platform-tools>fastboot flash recovery twrp-2.8.7.0-h
815.img
target reported max download size of 536870912 bytes
sending 'recovery' (32064 KB)...
OKAY [  1.197s]
writing 'recovery'...
OKAY [  0.317s]
finished. total time: 1.520s

C:\Users\~\Downloads\G4\platform-tools>fastboot boot twrp-2.8.7.0-h815.img
downloading 'boot.img'...
OKAY [  1.189s]
booting...
OKAY [  0.036s]
finished. total time: 1.230s

---

For me, it's ok, but after that, my G4 reboot directly to the system (Android 6.0 : V20A).

And when I run the command "adb reboot recovery" I get to a screen where there is only an Android slept with a red triangle and "No command."

Any idea please?

Kind regrards,
~~
Sylar

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