When we touch the screen nothing happens - changed batteries but still not working

This is usually cause by extremly hard impact which can dislodge the contacts between the Screen and its mating contact on the circuit board. This requires opening the device and attaching/repositioning the connector, whilst the divice is open you should place a small amount of hot glue on the outer part of the contact to prevent it moving. DO NOT use solvent based adhesives or super glue as this will severly damage the device. If this does not solve your problem contat me on [email protected] and I will try to assist you further.