Everything to do with credits is reachable from two places: the Billing & Usage tab in Settings, and the credit indicator in the header.

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Buy credits

You can purchase credits yourself. The flow opens as a panel over whichever screen you are on, so you do not lose your place.
1

Open the purchase panel

From any of three places:
  • Settings → Billing & Usage → Buy Credits
  • The credit indicator in the header, then Buy Credits
  • The Add credits button that replaces Send when your balance is too low for the message you are composing
2

Choose a package or enter a custom amount

Each package shows the number of credits, the price, and the effective price per credit. One package is marked as the most popular.To buy an amount that is not offered as a package, use Or enter a custom amount and type the number of credits.An order summary appears once an amount is selected, showing the credit cost, VAT and the total.
3

Enter your card details

Cardholder name, card number, expiry and CVC.The Pay button stays disabled until all four are complete and the expiry is a future date, so if it is not enabled, one of the fields is incomplete.
Card details are encrypted in transit and are not stored by Heullo.
4

Confirm

The panel confirms the credits added, your new balance, the amount charged and a transaction reference. A receipt is sent to your account email address.
Your balance updates immediately across the application — the header indicator, this tab and the purchase panel all refresh together.
An administrator can also add credits to your account directly, which is how accounts are funded when purchasing is handled through your Primetel account manager rather than by card.

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Check your balance and usage

The credit indicator in the header opens a Credits & Usage panel showing: The period can be set to hourly, daily, weekly, monthly, quarterly or yearly. The table below breaks down each period by messages sent, credits used, and successes against failures.
If the credit indicator is missing from the header entirely, the balance could not be retrieved. That is different from a zero balance. Reload the page before assuming you are out of credits.

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Review your transaction history

Two routes, showing the same ledger:
  • The account avatar in the header
  • The transactions table on Settings → Billing & Usage
The account avatar opens your transaction history. It is not a profile or account menu, and there is no dropdown — to edit your details, use Profile.
Each entry records: A summary strip above the table totals the credits and debits on the current page alongside your current balance.

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Reading your charges

A message charge records the part count and the cost per part, which is how to confirm why a message cost what it did. See Message encoding for what determines the part count.
Credits returned for unsuccessful messages appear as a Credit entry, and are included in the total added figure alongside purchases. For reconciliation, use the individual transactions and their descriptions rather than the summary total.

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Low balance alerts

Enable Low balance alerts on Profile to be notified before your balance runs out. This is worth setting up before running scheduled campaigns, which can otherwise stop part-way through.

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Troubleshooting

All four card fields must be complete, and the expiry must be a future date. The card number needs its full digit count and the CVC at least three digits.
Check the card details and try again. If it fails repeatedly, contact your Primetel account manager rather than retrying, so the attempts can be traced.
The balance refreshes automatically on a successful purchase. If it has not, reload the page. If the transaction appears in your history but the balance is unchanged, contact your account manager with the transaction reference.
The most common cause is the balance being exhausted mid-campaign. Top up, then resume the campaign from SMS Management. Recipients already processed are not sent to again.
Expected. Credits returned after failed messages are recorded as credits and are included in that figure. Your balance and the individual transactions are authoritative.