If you are seeing the 'Incorrect Format' error, then you are probably attempting to import your Secret Recovery Phrase using the Private Key importer. These are two different things, which is why the format is incorrect.
To import an additional seed phrase into your existing wallet, please follow the steps outlined in this article:
How to import multiple seed phrases into Phantom?
DO NOT share your Secret Recovery Phrase with anyone! If someone has access to your secret phrase, they will have access to your wallet. Phantom support will NEVER ask you for your secret phrase or your private key.