Help!Help!,Why this Scripts can't run in 3.11

RouterOS Scripting
1 
:local RbitNeiSum 0
/interface monitor-traffic WAN once do={:set RbitNeiSum($received-bits-per-second)}
:log info ("wan " . $RbitNeiSum)

thank you all

2 
:local RbitNeiSum 0
/interface monitor-traffic WAN once do={:set RbitNeiSum($"received-bits-per-second")}
:log info ("wan " . $RbitNeiSum)
3

thank you