# Redeem / Top up a card

We call the change in balance of a card a "balance adjustment. So to create a redemption, make a mutation request to `createBalanceAdjustment` with a negative value, or pass in a positive value if you want to top up a cards value.

{% tabs %}
{% tab title="API call" %}

```graphql
mutation CreateBalanceAdjustment {
    createBalanceAdjustment(
        currency: "GBP"
        value: -1000
        merchant_id: 26
        unit_epos_reference: "2251799825000010"
        card_reference: "6301190088474564102"
        merchant_transaction_reference: "ABC-DEF-GHI-1234123-123-0033"
    ) {
        id
        value
        LineItem {
            id
            Card {
                card_reference
                card_alias_card_reference
                balance
                expiry_time
                product_name
            }
        }
        ValueSplit {
            tender
            discount
        }
    }
}

```

{% endtab %}
{% endtabs %}


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