UPDATE: I did everything correctly. I need to fetch the token this way

@GetMapping("/profile")
    public Map<String, Object> profile(OAuth2AuthenticationToken auth,
                                       @RegisteredOAuth2AuthorizedClient("cognito")
                                       OAuth2AuthorizedClient client) {


        OidcIdToken idToken = ((OidcUser) auth.getPrincipal()).getIdToken();
        String sector     = idToken.getClaimAsString("custom:sector");


        String idJwt      = idToken.getTokenValue();
        String accessJwt  = client.getAccessToken().getTokenValue();

        return Map.of("sector", sector,
                "idToken", idJwt,
                "accessToken", accessJwt);
    }