It's probably because your Terra station wallet is set to mainnet by default. Try changing to the Classic network by clicking on the settings button and see if the coins appear in your wallet.

Did I needed to put a memo ?
No
second question : why when restoring the wallet do I need the password ? It's so stupid that private key alone isn't enough..
Thanks
The password helps encrypt your wallet if someone accesses your device and tried to access your wallet. Private key won't help with that kind of security.