I know it may be too late. Try turning the phone off and then on. Hold down the bottom button until the screen shuts off and then hit it again to turn it on. If that doesnt work try resetting it again.
First go into advanced settings and un register the handset from the base.
Then press 9#9#9* Hold then scroll to reset handset and press okay.
Then you will have to unplug your base for a few seconds and plug it back in to open it for registration and re-register the handset.
If that doesnt work you may want to enter the same code and then scroll to reset base and then reset the phone again and re-register it again. BEWARE: if you reset the base you WILL lose all numbers saved into the phone.
If this doesn't work you should send it back for repair with the base