Hello and welcome to Android Forums. Hopefully I can help you with your problem.
Turn your device off and pull the battery for aprox 2 minutes. Reboot the device and try again. You can also try a factory reset.
There is a chance you have issues with your bluetooth hardware too.
Without knowing your device specifics ( make and model ), it is difficult to troubleshoot.
If you have any other questions regarding your device, I invite you to join Android Forums. We have many sections for specific devices. Most contain a wealth of information.