What is the subnet that you are using for a gateway? You can choose some other IP address with which you will do the VIP. Can you please share the related configuration for the VIP that you are trying to use? Interface, static route, VIP policy, firewall policy, static route?
Since I am asking you to provide parts of the configuration, some malicious user can read this, so you can mask the real IPs or use trusted host.
As I said two years ago, if you "found that the same Public IP is defined as Gateway Address", "That generally means the static route was misconfigured whoever configured it. You need to judge if you can/should remove it based on the destination subnet."
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