One credit represents one message successfully sent by SMS or WhatsApp. Only SMS and WhatsApp use credits. Email and push notifications do not use credits.
Applicable plans include a monthly allowance. WaitQ uses that allowance first. Additional credits, when the account has them, are consumed after the monthly balance runs out.
Monthly credits refresh every month during the subscription, including on annual billing; the Usage period on Billing shows the current window. Additional credits remain in the account over time and do not reset each month.
When no SMS/WhatsApp credits are left, a call notification is sent by email when the customer has an email address; otherwise the customer does not receive a message. The staff confirmation explains which happened.
Open Billing to check SMS/WhatsApp credits per month and the remaining additional credits. Test messages use credits when they are actually sent.