Generate custom exception for schema validation

[mayankagrawalcts]

I have started using the "graphql-dgs-extended-validation" latest version. I was trying to generate custom schema validation exception logic however could not get success. can you please share any link or info to generate custom exception GraphQL exception for schema validation.
I have tried using https://netflix.github.io/dgs/error-handling/#mapping-custom-exceptions however it can handle only logical error not schema validation exceptions