Duplicate balances at Yoroi Shelley

I have created 2 wallets in Yoroi Shelley + Trezor, when I transfer my balance from my Yoroi Byron to these two wallets to include different amounts in each one, I transfer the same amount to the 2 wallets. What happen?
I transfer an amount of ADA from my Yoroi Byron wallet to one of my Yoroi Shelley wallets created today (Yoroi + Trezor) and that amount is reflected and transferred in the two wallets. Why? :shushing_face: