Some of these answers are a bit wayward:

On Proof of Stake protocols wallets and nodes, Orphan blocks are blocks or mints that are generated by the local client but not accepted on the network, this could be because another 'peer' beat you too in with their hash being accepted before yours, sometimes network latency can cause this (slow internet etc) and also sometimes could be because of a node problem, sometimes the time on the local client can be out by a few seconds and so does not sync correctly - if you see a succession of orphan mints, restart your client and also from console do getstakingstatus after wallet is unlocked and green check mark is showing as it can be the internal RPC commands are reporting differently to the external UI.

Orphon mints are generally thought of as lost but sometimes they do come back and are accepted, hours and days later, so don't give up hope on that orphan mint, you may see it get accepted in time!