how to fix running toilet

[kool]

water inlet is fine , water is running in the toilet bowl , not in the tank
see the pic
thanks

[hon]

Have you try changing the rubber casket (the black rubber ring).  Take it out and go hardware shop to buy a matching ring.

[kool]

yes thts the one need to be changed but i donno how to take it out

[basilleaf]

You better get a professional plumber.  We had a similar problem and we let it alone initially.  It became more serious and the water bill ran up to >$300 for that month Advice is to get it fix fast.  My plumber charged me under $100.