Rxsr recever to D 8 1-8 ch

I have the r xsr receiver in a diet tune 239 NX rabbit. I have it bound In D16 from 1 to 8 channels.
I have been trying to bind it in the D 8 1-8 channels and it’s not binding it’s unsuccessful why is this ?

Check the firmware on your taranis and receiver are both up to date and both either LBT firmware, or international firmware.

Okay thank you for the advice