Welcome to Android Central forums. I have a few questions before we can help you.
What device do you have?
When you say "keypad screen" what do you mean? Where are you finding this screen, what are you doing on this screen?
When you say you need it to last longer, do you mean you need the screen to be awake longer? Do you mean you need the keypad/keyboard to stay on the screen longer? Do you mean you need longer to input your (pin, code) before the screen times out? Describe what you need in detail please.
Is this for an app or the phone? If this is for an app, you'll get better results reaching out to the developer and asking to have a function added or checking to see if an option is available. We would have no control of things like that. If for the device, have you checked the settings for timeouts and screen locks to see if this option is available. Again if this is not an option, we cannot add it to your device.
Finally if you tell us in detail what the issue is perhaps we can offer you other solutions or work arounds if what you're looking for is not possible.
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