Does the pipeline settings JSON includes the "schema" field.
If you have full admin rights, you can update the existing pipeline settings to include the "schema" field.
Like
curl -X PATCH https://<databricks-instance>/api/2.0/pipelines/<pipeline-id> \
-H "Authorization: Bearer <your-access-token>" \
-H "Content-Type: application/json" \
-d '{
"schema": "your_default_schema"
}'
https://docs.databricks.com/en/delta-live-tables/properties.html
**schema
**
Type: string
The name of the default schema for the pipeline, where all datasets and metadata for the pipeline are published by default. See Set the target catalog and schema.