Shopping Cart Price Rule not working

[denialdesign]

I've set up a shopping cart price rule for £10 off an order and it's not applying properly at the checkout.

The cart page shows the correct total but the checkout does not. I've tried with PayPal, Check / Money order, with default theme, with RWD theme.The discount shows when I turn on "checkout with multiple addresses" and go through that checkout.

[denialdesign · Accepted solution]

Found the problem. The site was running php 7.0

Updated to 7.2 and everything works ok again.