Why softether vpnclient sends ARP requests from nonexist IP-address?

[spp]

tcpdump -n -i br1 | grep 172\.31

11:44:46.395667 ARP, Request who-has 192.168.192.34 tell 172.31.49.254, length 28
11:44:46.779639 ARP, Request who-has 192.168.192.40 tell 172.31.49.254, length 28
11:44:49.340736 ARP, Request who-has 172.20.172.3 tell 172.31.1.251, length 28
11:44:49.952577 ARP, Request who-has 172.20.172.3 tell 172.31.49.254, length 28
11:44:51.104762 ARP, Request who-has 172.20.172.10 tell 172.31.49.254, length 28
11:44:51.216142 ARP, Request who-has 172.20.172.10 tell 172.31.1.251, length 28
11:44:51.489015 ARP, Request who-has 192.168.192.34 tell 172.31.49.254, length 28

arp -an | grep 172\.31

? (172.31.1.251) at 00:ae:00:fa:6d:92 [ether] on br1
? (172.31.149.165) at 00:ae:94:a4:73:ed [ether] on br1
? (172.31.49.254) at 00:ae:30:fd:0a:49 [ether] on br1
? (172.31.170.145) at 00:ae:a9:90:13:79 [ether] on br1
? (172.31.126.85) at 00:ae:7d:54:fe:c3 [ether] on br1

Restarting the vpnclient changes these IP-addresses.

This network does not have 172.31.0.0/16 subnet

How to turn off this behavior?

[solo]

https://www.softether.org/4-docs/1-manu ... ll_Packets

[spp]

In certain network configurations (such as my case) softether cannot receive reply and continues to flooding the L2 segment with bogus ARP requests.

Server config option "NoArpPolling true" to disable this.