This is probably due to an incorrect operation.

You can partially reset your alarm system as by following the steps:
1) Turn your alarm of and then turn it on again;

2) After waiting for around 5 seconds, insert the reset code (88008800);
2) Afterwards, press the "Disarm" button for around 5 seconds until you hear a confirmation beep.

Then, to install the product, you must:
1) First, check if the SIM card installed in the GSM main unit is not protected by a PIN code and it has calling credit;
2) Insert the SIM card into the GSM main unit;
3) Power up the main unit and press the "ON" button;
4) Wait for the GSM indicator to start to flash every 3 seconds;
5) Download the mobile app and create an account by choosing a name for the alarm and then entering the telephone number of the main unit SIM card. (It is better to enter to the international calling code if you want to use it from abroad (e.g. 0044 for the UK. Do not use the format + (44)))

You can insert 5 telephone numbers for adjusting the main unit and be only warned in case of alarm (so you must add 0032 to these numbers).

To fully reset the GSM main unit, you must proceed as follows:
1) Turn off the alarm by pressing the button on the rear of the main unit.
2) Turn it on again and wait about 5 seconds before entering the reset code below
3) Enter the reset code (88008800), then hold down the disarm button for about 5 seconds until you a beeping noise;
4) Access the app and retry the connection.