Hi @kingsleych86979
Since there's no display on the external monitor either it may be that the laptop is not even starting and passing POST (power on self test).
Did you try a ''reset'' as suggested as you didn't say?
If it still doesn't work after doing this, sometimes a full power reset may be required. Be aware that doing this means that you have to disassemble the laptop.
Here’s the procedure:
Disconnect the charger from the laptop.
Remove the main battery from the laptop.
Remove the RTC coin cell battery from the motherboard.
Here’s the [link|http://h10032.www1.hp.com/ctg/Manual/c04825510.pdf|maintenance and service guide] for the laptop. Go to p.33 & p.63 to view the necessary pre-requisite steps and then the procedure to remove the main battery and the RTC battery, respectively. When the RTC battery is removed, measure its voltage. If it is <2.4V DC replace it or if it is >5 years old replace it anyway. Search online for 826388-001 or check what th ebattery type is as shown on the battery itself. It looks like it may be a CR2032.
Reinsert the RTC coin cell battery, re-assemble the laptop, re-insert the main battery, connect the charger to the laptop and try to start it.
If it starts, there may be a message about the date and time being incorrect. This is normal as the above procedure has reset the BIOS back to its factory defaults. Once the date and time have been adjusted, the message won't appear the next time the laptop is started. Any user defined BIOS settings that have been altered by you to suit your particular requirements will need to be changed back also.