Radio and cigarette lighter of Clio 1

Hi
I drive a Renault Clio 1 (2001 model). My radio kept making a beep sound and switching off after a few minutes. I did some research and found out that if the cigarette lighter doesnt work then it is a fuse as those two run on the same fuse. That solved all my radio problems, but everytime I push the cigarette lighter or plug in a charger of any kind the fuse pops again.
Can anybody please tell me what the cause of this might be.
Please help