Error message changing DNS

Warning: Multiple default gateways are intended to provide redundancy to a
single network such as and Intranet or the Internet. They will not function
properly when the gateways are on two separate, disjoint networks (such as
one on your intranet and one on the Internet). Do you want to save this
configuration?

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It's telling you to remove the default gateway from one of your connections as you should only have one.
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But that error message is still saying you are connected to two different networks.
Reset everything temporarily to dynamic and then run an ipconfig. What are the numbers? Does your router allow you to reserve an ip address for a specific network adapter? Might be a better way to go
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