Sorry If I ask you a stupid question but my ledger’s seed phrase is the same of Elrond wallet?

It’s a new ledger and I create a elrond’s wallet on it

Let's have a talk It will be solved

The seed phrase can be used to create wallets :) If you were to use the web wallet to restore your account with the seedphrase from the ledger you would get the same account. So to not undermine the security of your ledger you should never ever have the seedphrase anywhere digitally and you should also not use an existing seedphrase, but instead let the ledger generate it for you, for maximal security :)