so yeah i just bought a second hand iPhone 4s...i put in my sim which i just got that day,i bam i look up at where the signal bars are and they are all just flat...also with the wifi the on button is greyed out and there is nothing i can do to change that..ive tried so much stuff to fix these such as on/off.....rebooting...restoring....and reseting the network settings .....please help mee!