My laptop completely ran out of battery after 2 months of no use / no charging (I left it under the bed). When I tried to start it and didn’t work so I used the alt/shift/ctrl/power button technique. Took it a while but finally came back. Used it one day with no problems (plugged and unplugged) and the third day of use it started to shut down randomly (sometimes while loading the profile just after starting it). Is there any suggestion on what could be wrong or what to do?