We use various SMS providers for SMS routing to your guests:
Twilio, Nexmo, Retarus and Gateway API
On a per Tenant and/or per country basis, we may choose to use a certain provider over another for improved reliability. That choice is only a preference, meaning they will be used first. If the SMS is not received, you may click 'Send Again' in the console, which will send an SMS through another provider.
If you notice that you need to click 'Send Again' many or every time(s), you can contact us so that we can analyze the issue to see if it's linked to the particular provider you are set up with, and make necessary adjustment. Note that if you would like us to take this further with our SMS provider, they require that we provide at least 3 different numbers, ideally with a mix of handsets (phone models) to whom this happened during the same time period.
Sometimes it can be a country-wide issue, there are some countries that deliver SMS more reliably than others. Most times it will only be the case for a day or two at most. We'll try to keep you informed if that's the case, but it's often discovered after the fact
On average, an SMS should be generated and received within 5 - 30 seconds. Past that time, we suggest you click 'Resend', the link will be the same, and the worst that can happen is the guest receives the same SMS twice in a row.
If the SMS is still not received afterwards, there is always the option to send the link by email, or to generate the link and send it via some other means.