Contact Ingest from CX Sales not loading any data

We created one ingest job from oracle sales cloud to oracle unity. The source object in sales cloud is Contact. Target object in unity is Customer. But the ingest job imports 0 objects. We reviewed the export job created by te ingest job in sales cloud, that has 0 records in the export file. However, we have contacts in sales cloud.
Thinking that we cannot import sales cloud contacts as customers in unity, we created one custom table in unity and tried the same, Still 0 records are migrated.