login before checkout

Hi,
I have had Woo-commerce on my website for about a year and everything was working perfectly, but suddenly yesterday I had a new issue and was hoping I would be able to get some help here.

When I visit my single product page as visitor (none registered user) and try to add the item to basket, it does not add anything to basket and I get a message on top of the screen stating ” Sorry, you must be logged in to checkout.” (I dont have this problem for logged in users, its only for people who hasn’t registered or logged into the website)

now I did not have this problem in the past. because I had checked the box to allow customers to create account on the checkout page in woo-commerce setting .

I had deactivated all plugins that was recently installed to see if I could find the problem but I had no luck.

Can anyone here help me out?

Thank you