How to set aud claim in access token

I am executing a request to the Keycloak server (version 20) with grant type “Authorization Code”. The request returns successfully. But the access token contains an “aud” claim which contains an array of entries : master-realm, our-custom-realm, account.

Why are there multiple entries?

Even if I specify an audience on the request it won’t get set on the returned access token?

I am using Helidon OIDC security provider in my microservice and this expects a single value for the aud claim.

How can I set/specify the aud claim in the access token?

Thanks in advance.