Why want my nextbook stay on

Hi,

Does it power off or it is just that the screen turns off?

When you have it working in the upright position, try playing some music (or any audio) on the tablet and check if it stops (i.e. powers off) or if it continues when you move the tablet (i.e. the screens turns off).

If the problem is that the screen turns off only, then perhaps the video flex cable connection to the systemboard may be loose.

Here’s a link to the ifixit Nextbook NX008HD8G Screen Replacement guide which may be of some help to gain access to the connector so that it can be checked.

If it powers off here’s a link to the ifixit Nextbook NX008HD8G guides which should allow you to inspect other possibilities such as a loose or dry solder joint battery connection