i'm using Paypal Express Checkout in website , the problem that i'can process any payments all orders goes to Abandoned Shopping Cart with the messages :
NB/ When i hit complete in my website order and login with a paypal account button here the error message from :
We can not make your purchase for now
Return to the merchant site and choose another payment method
Don here from Shopify!
There's not a lot we can tell from here about what might be happening with your PayPal gateway, but not to worry.
You can reach out to PayPal support who will be able to see your account settings and information in order to be able to help out.
I did manage to find this forum article from the PayPal community which deals with this error, though it looks like in that case they needed to contact PayPal support any way to look into their account settings.
All the best!