cant use two accounts simultaneously in voyage is it possible? and I have one doubt how can logout with default which app itself created with seedphrase how relogin into voyage with same old account?
Your seed phrase is the private key. You need to find an app that will let you log in with it. I think nostr:npub1gcxzte5zlkncx26j68ez60fzkvtkm9e0vrwdcvsjakxf9mu9qewqlfnj5z is working on it for Amethyst. I hope nostr:npub1w4uswmv6lu9yel005l3qgheysmr7tk9uvwluddznju3nuxalevvs2d0jr5 will implement it in Amber.
Voyage is external signer (Amber) only, so you can't log in with seed phrase/nsec. We only generate a seed phrase so new users can directly start to use the app without figuring out what an external signer is.
Discussion
> cant use two accounts sulimultaneously...
No, not yet. I will implement multi account support eventually.
> how relogin into voyage with same old account
If you press logout you will be back to the account Voyage created for you. But if you uninstall and then reinstall the app the account would be lost. Unless you wrote down your seed and imported it into an external signer.