Once a transaction has been sent, the transaction is irreversible and cannot be cancelled. This is the way cryptocurrencies are designed, which applies not just to Edge, but to all other wallets and services as well.

You will need to contact the website, business, or person that you sent the funds to and provide them with your transaction ID, which is essentially a receipt or proof of payment. Let them know that you sent funds to them and that you would like to have the transaction refunded. The transaction ID can be found by tapping on the transaction you would like refunded, which is located within the wallet that the funds were sent from. After tapping on this transaction, you will tap View Advanced Transaction Data. This will open another window that will show the transaction details, and is the relevant link to send as proof that the payment was made.