magento2 – Update the select attribute in custom_attributes via the catalogProductRepositoryV1 API PUT request

I'm trying to update a product with the catalogProductRepositoryV1.
I want to modify a custom select attribute for the given product. When sending the following query:

{
"product": {
"Custom_attributes": [
            {
                "attribute_code": "color_armrest",
                "value": "Akoya"
            }
        ]
    }
}

I receive the following error:

{
"message": "An error occurred while processing " custom_attributes  ". The " color_armrest  "attribute has an invalid value. The type of the " Akoya  "value is incorrect type  "int " was expected Check and try again. ",
"trace": null
}

I understand that I am supposed to insert the option_id attributes here and not the label, but how do I get it? Do I really need to use the catalogProductAttributeOptionManagementV1 extract all the attribute options and filter the ID, then forward it to the product's request for sale?

cordially