WireMock

Is it possible to send a specific response incase there non of the stubs are matched against the incoming request?

Not really.  You are probably better off creating a catch all stub with a much lower priority than the rest

I see, any example for doing that, I mean how do we set priority?

<https://wiremock.org/docs/stubbing/#stub-priority>

Ah, yes, it says so in the docs - When unspecified, stubs default to a priority of `5`<https://github.com/wiremock/wiremock/blob/master/src/main/java/com/github/tomakehurst/wiremock/stubbing/StubMapping.java#L37|^> where `1` is the highest priority and Java `Integer.MAX_VALUE` (i.e., `2147483647`) is the minimum priority.