Hi there and welcome
This is a lock that someone on the phone has set there at one stage. Generally this is the same code as used if the screen lock is on.
Do you have a screen lock on the phone?
ok, then someone set it with a different code.
The only way to remove this code is a reset of the phone, which will remove all the data from the phone and return it to new, but you cannot avoid it with the security codes, so first backup anything from the phone first.
Then connect the phone to the computer and open iTunes (you can install it from www.itunes.com if you do not have it)
Hold on the phone the power and volume down buttons until you see a message indicating iTunes has detected a phone in recovery mode.
Then choose restore.
Once done, let it complete, the phone is reinstalled as new and you can set it up again.
The code will then be removed
Let me know please how you go.
it depends on your internet speed as it downloads the image, but on average an hour
you're most welcome
If you would like any additional information or assistance, please do not hesitate to let me know.
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