I am familiar with those settings, and this issue does not happen to any other win10 outside my local network.
This happens only to my local network, and cannot change it now to 192.168. because it is complicated
but the question is why the F5 decides to route my local network 128.0.0.0 to its VPN gateway ?
I contacted TAC and they asked to gather some logs from CTU... but they still investigating this issue
It worth mentioning that this is issue not not occur if using browser with network connect enabled after the connection established. This issue only happens with BigIP Edge Client.