The {exp:store:checkout} tag has stopped working.
What it does
When you proceed to the next step, or otherwise "Submit" the checkout tag it reloads the page and goes back to the beginning
What it should do
Go to the next stage or payment provider (depending on step)
Diagnosis Made
Thinking it may be our template, we looked at the example store sample templates included. The same problem is occurring there.
This site did, until recently work and no changes were as far as I can see made. There has been no sales in a week.
Software
We are running EE 2.5.2 with Store 1.5.3. We tried to upgrade to 1.6.2 but the following errors occurred. Could they be related? http://pastebin.com/JqTLdTX6