Access OIC instance from VB Application

Hi,

It supposed that Visual builder application should be able to connect OIC Integrations through "Services Catalog" ⇒ "Integrations Application". However, It raises for me this error

Additionally, I checked the Integration Application Backend settings and I found it raises the following error for the server's URL

I found Note from Oracle mentioning that error caused by invalid integration instance URL that should be corrected in VB Backend definition, however, this is the correct, the working and the default OIC instance URL coming with Oracle Visual Builder. How could we solve this issue?

Thanks,

Taha