P0513 - wont start after sitting for 3-4 mos. p0513 and p0562 syst volt low. Is there way to fix without towing in?

Question

let car sit...battery went dead...charged battery but still wont start...only have one key...have changed battery in fob...remote access in fob did not work prior to this. Ran diagnostics and got p0513 incorrect immobilizer key and p0562 sytem voltage low