Hi @arduan ,
Please verify that there is there only one light but two fan?
Supply an image of the light/fan switches. Here's how to do this iFixitでの質問に画像を追加する方法
If there are 3 switches then most likely the power for the light comes from the light switch and is also multipled down to the two other fan switches so that when they're operated the power is extended to the fans.
So in the switch plate if it has 3 switches there is the power wire coming in which connects to all the 3 switches and then each switch has a wire going out, one to the light, one to the fan and one to the other fan
Usually only the active wire is fed through the switches and the neutral wire (or L2 wire ) is fed directly to the light and the fans.
Be safety aware when removing the switch plate from the wall to check the wiring, as there is exposed potentially lethal voltage there. Remove the fuse for the lights in the premises in the power box and then double check that none of the lights work. Also check that there is no separate fuse for the fans just in case they are wired on a separate fuse feed. If in any doubt call an electrician, your life is worth more