To receive a text message on a rented number, you must first activate it in the "Rent phone numbers" - "My numbers" section. When you press the "Activate" button, the SIM card will start switching, the signal will be yellow.
SIM card switching can take a long time, it depends on the number of users waiting. When the signal becomes green, then the number is active and you can send sms on it.
After you sent an SMS to your number, wait in the "My numbers" section until the green "New SMS" button appears.
Customer support service by UserEcho