There are quite a few logical flaws in this code :|
first off
if (!getBank().open()) {
You will only enter this if-statement if the attempt to open the bank fails. Did you mean !getBank().isOpen() ?
Even if that is the case, doing something only if the bank is not open is a strange way to proceed.
next:
getBank().open();
if (getBank().contains("Lobster pot"))
getBank().open() will only do the interaction. It will not wait for the actual bank widget to appear. So odds are the bank is still not open when you check for the lobster pot.
getBank().getItem("Lobster pot");
This simply gets the item instance. It does not withdraw an item from the bank. To withdraw an item, use the withdraw methods.
while (!getBank().isOpen()) {
sleep(random(200, 300));
localWalker.walkPath(backFishing);
}
Not sure what to even say to this part. You walk back to the finishing spot in an eternal loop until the bank is open again? How is walking back to the fishing spot ever going to result in the bank opening? I can only see this piece of code locking the script
Try to revise it a bit; generally you should avoid doing multiple interactions in the same loop cycle, and also avoid potentially infinite loops.