Why the charger dont charge anymore?

I suppose you mean to say that the charger's USB plug isn't held snugly in the tablet's socket as it should be.

Both USB plugs and sockets are very delicate and easily damaged due to rough handling.

Try a different charger (you can use any USB charger, they are interchangeable) and see if this solves the problem. You can also use a USB cable connected to a computer's USB port to charge the tablet.

Leave the tablet switched off while you charge it, otherwise it might take a long time to charge fully.

If the problem persist when using a different charger or USB cable, the tablet's USB port is damaged and will need to be replaced. The USB port sits directly on the tablet's main circuit board, and replacement requires advanced soldering skills and tools.