Because I don't know the specific network environment, I can only tell you two methods for you to try:

1. Private network address migration

Change your private network to a network segment, such as 172.0.0.0/24, and configure and use a DHCP server (address pool:172.0.0.50 ~172.0.0.100.

2. Open the defense manually

According to the situation you described, manually turn on broadcast message suppression on Flying Fish Star VE982, save the configuration and restart the router.

Then open the IP/MAC binding, which can prevent ARP attacks.

In addition, reading your log, I feel that it is not an intentional ARP attack, but it may be an ARP conflict in the network, but it may also be a bug of Feiyuxing VE982 equipment. Try to clear the ARP table entry on the device. The general command is clear arp, or save the configuration and restart the device.