Transaction not yet indexed

21d6FHePFCxyJJRR51PvjMuxsmbsWTRfvKHdf1xa5UhiZ1TmXoWoAkRVTFKq69TPh3pT5G36TPdKMB16C8HpGFC4

The transaction signature is valid but not yet indexed by this RPC node, or the transaction failed before inclusion.