I created a new ETH wallet on metamask. Why is the secret recovery phrase the same as the one for my old wallet?

Is this how it's supposed to work?

I have one main wallet with a recovery phrase. I wanted to create a new one and transfer my crypto into that. I downloaded the metamask ext because I'm on a new device. I recovered my old wallet using the recovery phrase. Then I created a new wallet. I went to go check the recovery phrase for the new wallet and it showed the same RP as for my old wallet.

This doesn't make any sense to me. For one thing, in the past, I made additional wallets connected to my main wallet in metamask. Why don't those show up when I use my RP ... Like I would assume those ones I created in the past (when I was logged into my main wallet) would have the same RP too