my bitcoin address was start with 1****
and after i received money to them, i found my address start with b******
First make sure you import the account with the same private key. You will of course receive your btc when you import the wallet with the original private key. Even if your wallet changes in this case. For example, in coinbase wallet, if you copy a bitcoin address by clicking (Received) once, and if you receive bitcoins at that address, then when you copy the wallet later, you will notice that the previous wallet has changed. But your bitcoins will be fine in the balance. Maybe that's how it works.
On the other hand, you should follow the guide provided by OmegaStarScream to see which of your SegWit and legacy is selected as default and which one you receive bitcoins.
Go to your Blockchain account -> "Wallets and addresses" page, find your wallet, I believe by default it's called "Private key wallet" then click "Manage". You should then be able to see both SegWit and legacy addresses.