Apple iPhone 3G - 8GB - Black (Unlocked) Smartphone FAULTY *

In a very good condition with some light scratches on the screen ! Normal cracks for apple around the charger ! Coming with box, charger, USB cable and earphones ! The slider for SIM works perfectly but need to be pushed with thin sharp object ! Important : It works with O2, giffgaff , Orange & vodafone sim , but doesnt make calls, and doesnt receive any incoming calls, dont know why, 2 months ago it worked perfectly ! Anyone interested let me know ! p.s : I think repair costs about 15-20 quids, but no time to do that as i have new 4s already !