Please I want to cancel my in review transaction on blockchain. How will I go about it. Please help me,I need answers as soon as possible.
You can't cancel a transaction. You can broadcast another transaction with a higher transaction fee (replace-by-fee) sending back to an address you own and hope that gets confirmed before the original transaction (miner is incentivized to mine this replacement transaction rather than the original one). Or alternatively you can ask the recipient to send the funds back to you after it has been confirmed. But once you have broadcast a transaction there is no way of cancelling it and instantly removing it from other people's mempools.