Since you have an orange light, this system has most likely been off for quite some time resulting in the battery being drained. Just leave it plugged in overnight and your problem will most likely be fixed.
Also, Since you bought this PSVITA used, it is probably linked to the previous owners PSN account. to reset the system to factory settings you will need to hold the Power Home and PS button. after that select reset to factory settings.
Let me know if this works for you and if you need anything feel free to send me an email at tyler.hoban@gmail.com
I hope this info fixes your problem.