Aspire A315-23 keyboard and trackpad not working

Monannn

Hi guys.
I purchased A315-23 Ryzen 5 (3500u) about 3 month ago.
Because it was working hot, i brought it to the service center (not authorised) and they changed thermal paste. 
After turning on the laptop just after changing thermal paste at front on me, neither keyboard nor trackpad working. (All other components works fine , eg: usb port,... ).
Power button working !! But all other keys are dead!
Windows is booting normally. (But in device manager shows a error for both of them. All deivers are update).
Note: it is not working from boot! Not possible to enter bios!! 
It's very weired! How it would be possible that trackpad and keyboard fail at the same time???

Anybody have any idea?
Is it need to repair something or totally change the keyboard and trackpad?

Thanks

JackE

You must return it to the service center as it sounds like the keyboard and trackpad cables have come loose from the mainboard. Jack E/NJ