The sound in my Bush TV stopped suddenly after using head phone in the TV. What should I do to make it work?

Have you tried to "power down" (unplug, wait, then re-plug) the TV?
That might allow it to reset.

Which model do you have?

There is a switch in the headphone plug that turns the sound off to the speakers when the headphones are plugged in. It probably has dirt on the contact keeping the speakers off. This is a very simple fix after you get to the plug.