Do you have a data plan on your phone? If not, then you won't be able to access the anything on the laptop. Also, if the plan is restricted by the carrier/service provider, that could also cause this.
If you do have data on the phone, and you have confirmed with your carrier/service provider that there are no limitations on the data access, then you can try shutting down the hotspot and restarting (turning off and back on) the phone. Then turn on your phone's hotspot again. The same way you would connect to any WiFi.
On the laptop, forget the hotspot info, reboot the computer (turn it off and back on) and then try to connect to the hotspot again.