When creating a new item, you can pass 1 field only:
After submitting the POST request, a new Item is created with a status of CRAWLING.
While status is CRAWLING, the Item is in a read-only state - no fields can be modified. The Item should be polled repeatedly until its status changes. (Every 10 seconds is a reasonable polling interval.)
Once the Item status changes from CRAWLING, it can be edited.
Once crawling is complete, status changes to PENDING.
Once approved by Taboola, status changes to RUNNING.
If you edit one of the fields, status changes to PENDING (until approved by Taboola).