What did you do? The description is not helpful.
Do you have a router?
If you have a router what did you change, the private or the public IP address?
If you changed the private address this was foolish, go back to obtaining IP address automatically.
If you changed the public address, this was even more foolish, go back to the static IP the ISP gave you or to the dynamic you should have.
If you have no router, follow the same directions for public address on router.
If you have no idea what you are doing, don't play with things. Clearly you have at best a very limited idea of what you are doing.