Best Practices for handling message processing failures (Go API)

Hi, just wanted to know what is the best practice for handling failures when processing consumed events from a queue?

i.e. Upon consumption of an event from a queue subscribed to multiple topics, I would call an external API to send an email to a person based on the topic. However there is a chance that this API call would fail, and I would like to retry this event.

What would be the best practices in this case to attempt a retry a certain number of times before publishing to a dead letter queue?

var notificationReceiver solace.PersistentMessageReceiver

func initNotificationSubscriber(msgService solace.MessagingService) error {
    notificationReceiver, err := msgService.CreatePersistentMessageReceiverBuilder().
        WithMissingResourcesCreationStrategy(strategy).
        WithMessageClientAcknowledgement().
        WithSubscriptions(ts...).
        Build(queue)
}

func notificationMessageHandler(message message.InboundMessage) {
    var messageBody []byte
    if payload, ok := message.GetPayloadAsBytes(); ok {
        messageBody = payload
    }
    receivedTopic := message.GetDestinationName()
    slice := strings.Split(receivedTopic, "/")
    switch slice[0] {
    case "payment":
        switch slice[1] {
        case "failed":
            if err := sendEmail(messageBody, "failed"); err != nil {
                // Want to retry this here
            }
        case "success":
            if err := sendEmail(messageBody, "success"); err != nil {
                // Want to retry this here
            }
    }
    notificationReceiver.Ack(message)
}