[alykins]

You never substantiate store, you just declare it. It's not a datatype so it needs to be substantiated- you've only created a singleton

private Store store; //singleton
.......
//elsewhere
private someFxn()
{
  store = new Store();
  // now store is usable
}

which let's you do things like

private Store store;
.....
private someFxn()
{
  for(int i=0; i<10; i++)
  {
     store = new Store();
     using (store)
     {
         /// do something
     }
   }
}

without throwing an error (note idk what the java equivalent is to using in C#)

because if you did this

private Store store = new store();
.....
private someFxn()
{
  for(int i=0; i<10; i++)
  {
     using (store)
     {
         /// do something
     }
   }
}

it would go through the loop once, destroy it and then throw a null exception