Try adding once-per-request="true" filter-all-dispatcher-types="false" use-authorization-manager="false" with http

<http pattern="/admin/**" once-per-request="true" filter-all-dispatcher-types="false" use-authorization-manager="false">
    <custom-filter ref="myLoginFormAuthenticationFilter" position="FORM_LOGIN_FILTER"/>
    ...
</http>

Migration Ref: - https://docs.spring.io/spring-security/reference/6.0/migration/servlet/authorization.html#_use_authorizationmanager_for_request_security