I am the custodial parent as of now and I reside in ny. My daughter moved back with her mother who resides in virginia. Her mother was paying child support but it stopped (which I don't understand why). She doesn't have residential custody yet. We wanted to see how it would work out for my daughter first. The support order is in ny but they live in virginia. Shouldn't the support order be with virginia?

No. The order must be honored in Virginia until and if it is modified. She still has a duty to continue paying support until then.