SMS reminders are a powerful tool for keeping your customers informed and engaged, but if your customers are not receiving them, the issue is usually caused by the phone number format, by the message being blocked on the customer’s phone, or by a missing SMS credit balance.
The importance of including the country code
A common reason for SMS delivery failure is the absence of the country code in the phone number. Please note that the inclusion of the country code is essential for the SMS to be delivered by our SMS provider.
To ensure the successful delivery of SMS reminders, all phone numbers must be entered in the E.164 international format, which includes the country code followed by the phone number.
Correct format for phone numbers
Ensure that the number starts with a "+" followed by the country code and then the mobile phone number.
No spaces or other special characters (e.g., parentheses, dashes) should be used.
Here is a list of country codes for some commonly used countries:
Here is a list of country codes for some commonly used countries:
Brazil: +55
Czech Republic: +420
Denmark: +45
Finland: +358
France: +33
Germany: +49
Italy: +39
Netherlands: +31
Norway: +47
Poland: +48
Slovakia: +421
Spain: +34
Sweden: +46
United Kingdom: +44
United States: +1
If the phone numbers are not updated to follow this format, SMS notifications will not be delivered.
The sender InfoSMS is blocked on the customer’s phone
All SMS notifications sent from Reservio are always delivered under the sender name InfoSMS. This sender name cannot be changed.
If your customer has blocked the sender InfoSMS (directly on their phone or through their mobile operator), our SMS reminders will never reach them, even though the message was sent successfully from our side.
Some smartphones block or filter these messages automatically. Because InfoSMS is not a contact saved in the phone’s address book, the message can be marked as spam and moved to a Spam, Junk, or Filtered messages folder, where the customer will not see any notification about it.
Ask your customer to check the spam or filtered messages folder in their SMS app, and to unblock or allow messages from the sender InfoSMS.
There are no SMS credits left in your account
SMS reminders are only sent while your account has a sufficient SMS credit balance. Once the credits run out, no further SMS notifications are sent to your customers, and the phone number format makes no difference.
Check your remaining SMS credit balance in your Reservio account.
Top up your credits to resume sending SMS reminders.
How to resolve the issue
To address this problem, we recommend the following actions:
Manually update all stored phone numbers to comply with the required format (including the correct country code).
Provide clear instructions for customers to enter their phone numbers correctly when submitting them. This will help avoid formatting issues in the future.
Check your SMS credit balance and top it up if you have run out of credits.
Ask the customer to check their spam or blocked messages and to allow messages from the sender InfoSMS.
By ensuring that phone numbers are formatted correctly, that your account has enough SMS credits, and that the sender InfoSMS is not blocked on the customer’s phone, you can help ensure that SMS reminders are delivered without issues.