Here is an instruction of performing soft reset and hard reset on Microsoft Lumia 540 Dual SIM smartphone. Just few things to check before performing hard reset.
01. Try to perform soft rest first before hard resetting.
02. Try to back up your phone. (Hard reset gin delete all files and settings)
03. Check your phone battery is charged more than 50%.
If you are ready to perform hard reset, let’s do it!
Soft Resetting
Step 01. Press and hold the Volume Down + Power keys at the same time for about 10 seconds until the phone vibrates.
Hard Resetting
Step 01. Shut down the device completely. (Press and hold the power button for few seconds and then slide down to turn it off)
Step 02. Press and Hold the Volume Down + Power buttons at the same time until the exclamation mark comes up on the screen.
Step 03. Now press buttons in the following order: Volume Up > Volume Down > Power > Volume Down.
Step 04. Once press the buttons, Microsoft Logo will appear on the screen and hard resetting starts to process. Please wait until the process is done.