how you like my glizzy son

oogla booga lookin like my glizzy

It's great, but it logs errors because there's no elements with the ids nextCost1 or nextCost2.
here I've commented out the bad lines

function BuySeniorHacker() {
  var SeniorCost = Math.floor(100 * Math.pow(1.2, Senior));
  if (Hacked >= SeniorCost) {
    Senior = Senior + 1;
    Hacked = Hacked - SeniorCost;
    HackPerClick = HackPerClick + 5;
    document.getElementById("Senior").innerHTML = Senior;
    document.getElementById("InfoHacked").innerHTML = Hacked;
    localStorage.setItem("Hacked", Hacked);
    localStorage.setItem("HackPerClick", HackPerClick);
    localStorage.setItem("Senior", Senior);
  }
  var nextCost1 = Math.floor(100 * Math.pow(1.2, Senior));
  document.getElementById("SeniorCost").innerHTML = nextCost1;
  //document.getElementById("nextCost1").innerHTML = SeniorCost;
  localStorage.setItem("nextCost1", nextCost1);
  localStorage.setItem("SeniorCost", SeniorCost);
}
function BuyProHacker() {
  var ProCost = Math.floor(1000 * Math.pow(1.2, Pro));
  if (Hacked >= ProCost) {
    Pro = Pro + 1;
    cps = cps + 5;
    HackPerClick = HackPerClick + 10;
    Hacked = Hacked - ProCost;
    document.getElementById("Pro").innerHTML = Pro;
    document.getElementById("InfoHacked").innerHTML = Hacked;
    localStorage.setItem("Hacked", Hacked);
    localStorage.setItem("Pro", Pro);
    localStorage.setItem("HackPerClick", HackPerClick);
    localStorage.setItem("cps", cps);
  }
  var nextCost2 = Math.floor(1000 * Math.pow(1.2, Pro));
  document.getElementById("ProCost").innerHTML = nextCost2;
  //document.getElementById("nextCost2").innerHTML = ProCost;
  localStorage.setItem("ProCost", ProCost);
  localStorage.setItem("nextCost2", nextCost2)
}