Why isn't the appliance working after I replaced the batteries?

There could be a number of reasons why the appliance isn't working. In this case, we assume that the appliance works properly.

The battery has been inserted incorrectly into the battery compartment. The appliance will not work if it is protected against reverse connection and the battery is inserted backwards. Please double-check that the batteries are properly inserted.
The battery and the compartment connection terminal are not connected properly. A battery compartment should normally be designed in accordance with IEC standards. However, sometimes this is not the case. It's possible that there's a bad connection between the connection terminal and the battery. The appliance may not function properly as a result.
Of course, there is the possibility that the appliance will not function properly. Please ensure that this is not the case.

A question? A request? Let us know.