Magic stove - Induction cooker
Some fault, help needed

The problem in my induction cooker is that, "When it is switched off by pressing the POWER button and the plug is "on"... its fan inside keeps on working...

But when it is directly switched off from the plug... it stops completely... so what should I do, coz the safety instructions in the manual book say that " I have to switch off by pressing the POWER button and then the plug...

What to do... If I continue..to switch it off just from the POWER button... would that be harmful for the product...