Given that you have an xpub and xprv, you appear to have an HD wallet with blockchain.info... so I'm guessing you should also have the 12 word recovery backup as well, correct?
If so, you could try using the BIP39 Mnemonic Code Converter (https://iancoleman.github.io/bip39/ - create offline copy etc), put in your seed, click the BIP44 tab... and see if it creates your addresses... if you see your "receive" address(es), try changing the "External/Internal" value to 1 (BIP44 derivation path: m/44'/0'/0'/1)... that should then generate your "change" addresses...
Same problem here!
I keep my BTCs in a cold wallet, which I enter the PK in the option of importing addresses from Blockchain.info, and transfer the desired amount to the exchange, moving the rest to another cold wallet that I create in bitaddress, I've been doing this for a while and I've never had problems.
To track the balance, I always enter the public key in blockchain.info (Watch Address), this time I saw that there was a 'Private Key' field on the screen below the Watch Address, allowing me to move my bitcoins right there, without having to import them.
I entered the private key in the field below the public key, put the exchange address and the value, imagining that the remaining balance would go to the main wallet.
However, the balance that was in the paper wallet: https://blockchain.info/en/address/1AXXCct4QATf2UdX92piw1AA2As8AoZaoM, was moved to change address: https://blockchain.info/en/address/1KfTVrLG376B7SYb1bA6NnY7KyK825T72B, which had 2 outputs, one for the exchange (1PjcZKMFR8wkFjoMAE2aoVfSeB5xHwVLdu) and another for herself.
But, this address does not have a private key (1KfTVrLG376B7SYb1bA6NnY7KyK825T72B), is appearing as Watch Only in Blockchain, I understand that it
would be a main wallet address containing change funds.
I have already tried to use the tool: https://iancoleman.github.io/bip39/, but the address 1KfTVrLG376B7SYb1bA6NnY7KyK825T72B are not there.
I tried to email them through the request address, but I do not think they'll respond there, what channel you used for this?
The value is low but it's all my savings, thank you for all your help.