Update variant main image via api

We have over 50000 products and variants. Veeqo selected the wrong main images for our products.

Trying to update images via API and only found this old change image thread from 2018

was able to retrieve sellable object

curl --request GET \\

–urlhttps://api.veeqo.com/sellables/xxxxxxxxx\
–header ‘accept: application/json’ \
–header ‘x-api-key: [APIKEY]’

tried to replace/update image with a put command

json payload

{
  "product": {
    "images_attributes": [
      {
        "src": "https://sourceURL",
        "display_position": 1
      }
    ]
  }
} 

but received a 400 error bad request