Now this not only applies to 2 gang switches but to all the switches or switch sockets in your house. It is common knowledge that if you are to get an skilled electrician to your house to replace that 2 gang switch or whatever other switches in your house, they either almost never comes of even if they do, they are really going to slash your throat to make their trip worthwhile. So it is best you learn how to replace that 2 gang switch or whatever other switches.
Most switches, when they gets spoiled, they gets spoiled. Don’t even bother trying to repair a faulty 2 gang switch. It will not be worth the trouble. Go to some electrical outlets and just get yourself a new one and a 2 gang switch will not cost you your month’s pay.
So, when you first do the electrical installation for our house, make sure you use switches, 2 gang or otherwise, that are readily available. Most branded ones, like MK, are very commonly used so getting the same one when you attempt to replace that 2 gang switch yourself will not be too difficult.
Always try to get the same brand when replacing. That way, all you need to memorise is the original terminal of the existing switch and terminate the new switch accordingly. If you get a 2 gang switch that is from a different manufacturer, they might have a different design and the terminal location might be a little bit different though it all works in the same way.
Take note that all switches have indications embedded near the terminal. Mots indicate the live wire, that is the wire carrying current to the switch as L1 and the wire that supplies the current to the light is indicated by L2. So even if you decide to get different brands, just make sure you remember which are the L1 wires and which are the L2 wires, but even if you git it wrong, there won’t be any problem. At most, either the light won’t light up or the lights cannot be switched off. The new 2 gang switch will not explode or anything.