Phones fall in lakes. When yours does, the ten recovery codes you stored at enrollment are the difference between a two-minute login and an incident. Each works exactly once — paste one into the code field and the console tells you how many remain. goca stores only keyed hashes, so it can never display them again; the moment to print them is the moment they are on screen.
Three related self-service paths, each requiring what it should. Rotate to a new phone with a code from the current authenticator — a recovery code deliberately will not substitute here, because a leaked code that could re-point your factor at somebody else's device would be a permanent takeover rather than a one-time way in. Confirming retires the old factor and every unused code, and issues ten fresh ones. Replace the codes alone after using some or printing them badly — the old ones stop working immediately. And watch the count: a low remaining-codes number is on the quarterly review list for a reason.
Now I can survive a lost phone without calling anyone.