I tried the default theme and deactivated everything but WooCommerce.
The strange thing is yesterday this was working fine. The only thing that has changed today is that a SSL has been issued but I haven’t had details yet to upload certificate, and I updated latest StoreFront, but I have a child theme so don’t see how the StoreFront update would affect anything.
Could the SSL be the issue and once I’ve set it up the checkout will work again? That is what my hoster is trying to say.
Thanks for you help.