rb750 rOS 4.16 , traffic flow , no flow ?

hi guys,

i’ve configure my rb750 for traffic flow..and i’m using PRTG freeware (10 sensors)

the ether1-gateway is connected to my VDSL modem which is connected to my isp…

but when i check in winbox traffic flow settings , status.. there is no flows, i even wiresharked my target computer and there is no udp traffic on port 1234 from my rb750

what am i doing wrong ?

[admin@] /ip traffic-flow> print
enabled: yes
interfaces: ether1-gateway
cache-entries: 4k
active-flow-timeout: 30m
inactive-flow-timeout: 15s
[admin@] /ip traffic-flow target> print
Flags: X - disabled

ADDRESS VERSION

0 192.168.88.100:1234 9
[admin@] /ip traffic-flow target>

but