I have no idea why this is happening. I can see the cart dropdown with products in it, but when I open "View and edit Cart", I get the error. If I refresh the page (the one that I came from, not the cart), I can still see item in the cart dropdown, yet the error persists.
I've taken a look at the database and there is a row in "quote" with an entity_id of 22.
So far the only way I've been able to do anything is to clear cookies. This isn't something that a customer should be expected to do. How do I fix this?