hi there,
we have the same problem.
costumers are unable to process their payment.
error notice is shown. there is no connection to paypal.
the problem started exactly 01. of july
so i assumed it has to do with security changes by paypal.
since then i am in contact with paypal support, without any luck.
our caching is disabled. this does not change anything.
we are using woo commerce with plugin woo commerce germanized.
the paypal plugin, which comes with woo commerce is working.
so i switched for that in the meantime.
this way costumers can at least pay with paypal, but logically no credit cards etc.
thx for helping