android wont boot but showing signs of charging

[AC Question]

hey guys
i have an android sony xperia u (pretty old i know) and a couple of days ago it ran out of battery, so i plugged it in and let it charge. when i went to see the progress, i saw that despite it showing the charging graphic it would still not turn on and after at least 12 hours of it being plugged in, it still wont boot. i tried holding down the volume and power button but nothing happened. i plugged it into my computer and its showing that its charging but its not booting and the computer isnt identifying it
i would just get a new one and that is also what im planning on doing but i have some really important contacts in there that i really dont want to lose so if i could manage to boot it up just enough to transfer my contacts that would be great
thanks everyone

 

[Golfdriver97]

Honestly, I don't know what to suggest. 12 hours should be enough to charge even a low battery. Is the battery replaceable? The battery may not even really be taking a charge, if it can't turn on...