Samsung Galaxy Core Prime User Manual page 295

Note: To change your unlock screen pattern, from home, tap Apps
Screen lock.
Use a Screen Unlock PIN
1. From the Screen lock settings menu, tap PIN.
2. Enter a PIN, tap Continue, re-enter your PIN, and tap OK to save the setting.
The screen lock is set.
If you fail to enter the correct PIN after five attempts, you will be prompted to wait for 30

seconds before you can try again.
Settings
> Settings > Lock Screen >
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