Help to get [/interface ethernet get ether1 rx-byte] !!

RouterOS Scripting
1

Hi
this script not work on mikrotik 6.15 :
:put [/interface ethernet get ether1 rx-byte]
why??
i’m tried another such as [/interface ethernet get ether1 driver-tx-byte]
but answer is empty or “nil”
thanks

2

:put [/interface ethernet get ether1 rx-bytes]

3