Problems modifying an asset in shopify using the node API

I’ve been struggling to solve a problem for 1 day, but I still can’t figure it out.
I’m trying to load 2 scripts in the header in shopify, but every time I try to do this through the api I get the error "Not Found"
I searched all the forums but I couldn’t find a solution

const asset = new shopify.api.rest.Asset({session: session});

            asset.theme_id = theme.id;

            asset.key = 'layout/theme.liquid';

            asset.value = `
              {{ content_for_header }}
              {{ ' ' | script_tag }}
              ${scripts}
              {{ ' ' | script_tag }}
              {{ content_for_layout }}
            `;

            await asset.save({
                update: true
            });

The path is correct, the theme id is correct, but I still get not found
When I try to find this asset

 [
2023-05-09 10:39:47 │ backend  │   Asset {
2023-05-09 10:39:47 │ backend  │     key: 'layout/theme.liquid',