Hi @mrhidden ,
After two years of non use and non charging, most probably the battery has become depleted beyond recovery and has failed.
Try replacing the battery and then check if the phone charges and works OK.
Here’s the ifixit [guide|79004] guide that may help with this.
Replacement batteries are available online. Just search for ''Huawei P9 Lite battery'' to get results for suppliers that suit you.