YSC receipt numbers are assigned to the USCIS Potamic Service Center. USCIS does not deal with visas, they handle petitions and applications. After approval of the petition, it will be sent to NVC for further processing, then sent to the embassy who can issue the visa. It's one workflow, but different departments of government (USCIS is under DHS, embassies are under DOS).
It typically takes a year or so from I-130 filing to embassy interview for a parent. Potamic is averaging ~6-7 months from NOA1 (receipt) to NOA2 (approval) for an immediate relative petition.
Sometimes the receipt numbers don't work on their online website. Unfortunately, that's just the way it is. You can call their customer service line to check on the status.
