Products Disappearing From Cart At Checkout

I have customers trying to checkout but the contents of their carts keep disappearing.

Has anyone else had this problem??

After my upgrade to 2.1.3 items are not showing in the cart side box and the shopping cart will not show on the home page. Everything was working fine before the upgrade, but something must have changed that is not showing on the local file modifications list. Any ideas would be appreciated.

I had a customer complain yesterday about this. This was the first time it occurred. No idea what browser she was using. She said it occurred after she hit the calculate shipping button

I had two customers complain on Monday. They could not stay logged in or keep items in the cart. I only heard back from one. She was using Safari and switched to Firefox to place her order without any further issues. I have no idea what’s going on.

Here’s my thread on it: