Flip Ultra hd wont start just got it today?

Okayso my lfip ultra hd wont start up i tryed putting the battery did everything the instructions told me but it wouldnt start up it is refurbished but dont you think it would of worked is there something to fix it i put the battery in the right direction i pressed the power button and it didnt turn on ive been waiting for my dad to buy this for 1 month but when it came in it didnt work :( please help