I can't say I've ever heard of the service, and like to think I usually have my finger on the pulse when it comes to indexers. Looks like they even had a sales thread in the marketplace back in the day (
https://www.blackhatworld.com/seo/w...ew-powerful-backlink-indexing-service.908586/). If you still have no response from the service you could try messaging the thread starter, but they don't look to have been online in over 12 months.
On the other hand, 4 days is quite short a time for testing an indexing service, especially with indexing the way it is today, so if you've opted for one of the cheaper packages you could ride it out for the month and see if anything gets indexed. Then report back so other forum members can share your success/pain