My laptop is suddenly shutting down

i've spilled water on my hp laptop about 2 weeks ago, i dried it and powered it up again and again but it keeps shutting down after 5minutes without any warning, i took it to a repair shop and they said that all the hardware is working fine and they don't know what's wrong with it.since it's the battery won't charge anymore i thought it was a power related issue and replaced the power socket it didn't fix the problem but i can use it now for about 2 hours before suddenly shutting down