Unless you are sure you are entering the correct passphrase and password, the same you used when you did $ safe auth create --test-coins, then the only explanation I can find is some other instance of the “no data found” issue some people are facing due to some chunks not being found and/or lost. If you can still reproduce it, please take look at the authd log at ~/.safe/authd/logs/sn_authd.log and see if you get one of these errors.
Yes, and yes, so try again, you don’t need authd to create SafeKeys with testcoins and transfer coins among them.
There has been a few attempts to rename this to something else, I think we didn’t find better name yet, this is supposed to be where you have a coin’s balance, some people said “wallet” but we also have the Wallet abstraction which is a container for many SafeKeys similar to other crypto wallets, so some said this is just an “address” but we already have xorname addresses, …if everybody think this is worth a change perhaps a new thread can be started to try to find a better name.