Ordered a root beer milkshake (my fav) and it was ...

Ordered a root beer milkshake (my fav) and it was super sour, with a weird after taste .It barely even tasted like root beer. I asked the cashier if this is what it should taste like and she said yes with a smile... She didn't try to accommodate or offer to remake it. Paid for a second drink.
And our food order was missed and completely forgotten about
Quality definitely has gone down