You may have entered a wrong phone number. Please check this, and re-enter your phone number if necessary.
Sometimes, it can take some time for a phone to actually receive a text message.
It is possible that a setting in your phone or at your telecom provider prevents you from receiving the SMS. We use A2P messages (Application-to-person) and sometimes these type of messages are rejected. Your provider can help you with checking this setting.
If you still don't receive the SMS message, please contact us.
In order for us to help you as quickly as possible, please send us your mobile phone number and mention the event you are attending or trying to buy tickets for.