I know, I double checked their address in Callback URL and the one in my files. Now also made that array with 4 more addresses which I used yesterday for testing and same results.
Why can't fire test callback also, related?
When you use the test callback what is the error given?
Now it's always "Invalid Server Response: Incorrect Receiving Address". Even when I test by myself and set GET parameter it's always the same no matter if really wrong address or not. I have no idea why is that... broken boolean lol. Also I have sent you codes on PM if you have time to check but there should be no problem because used fine on another server site.
My host fixed that problem but thanks for useful information

EDIT: Remembered .htaccess........