phillis Bunch, see if this will help. If that does not work, you will have to do a factory reset. REMEMBER that a factory reset will reset your Samsung Galaxy Tab to factory settings and all your data on the device will be erased.
The steps to do a hard reset are as follows:
1. With the device off, press and hold Volume Up and Power button.
2. Release the Power button when you see the Samsung logo, continue to hold Volume Up until the recovery screen appears.
3. Use the Volume buttons to navigate the menu and select wipe data / factory reset. Press Power to continue. The Galaxy Tab should then go through the hard reset process.
4. When formatting completed, navigate to select Reboot system and press Power. The Samsung Galaxy Tab is back to the factory
Hope this helps, good luck.