Do blockchain.info wallets correspond to a single wallet on the blockchain? To learn about bitcoin in a hands-on way, I decided to buy some. I created a wallet with blockchain.info, and then used Bitonic (A Dutch bitcoin seller, not an exchange) to buy a small amount of bitcoin. Later, I added some more.

So far, so good, the money arrived in my wallet, and I've been enjoying the recent surge.

However, I decided to use the blockchain explorer to have a look at what was actually happening during these transactions, and when I look at my wallet's address (the one I give to Bitonic), it's empty and there are are no transactions to it. Looking at the actual transactions that blockchain.info points to, there are outputs with the right amount, but they have different addresses.

I was expecting to find my wallet on the blockchain, with the current amount of BTC I own and two transactions going in.

What's happening here? Is Bitonic actually sending blockchain.info the coins off-chain? Bitonic only gets the wallet address, so they shouldn't be able to tell who manages the keypair for me. On the other hand, if bitonic sends it to the address I gave them, why does a different address show up on the transaction output? Is there some mapping between addresses going on inside the blockchain that I'm not aware of?
It's normal . Your blockchain.info wallet change the address in every transaction. You can learn more by google " bitcoin hd wallet".