Freezing the card through the app is an excellent and quick step, but it's not always the end of the matter.
If the card is actually lost or stolen, contact your bank to register the situation and find out if a permanent freeze and replacement card are required, as the meaning of "freeze" and the possibility of unfreezing vary depending on the bank and service.
CIB, for example, allows you to freeze a lost or stolen card through several channels, while the Central Bank requires you to notify the bank immediately upon loss.