We have resolved the issue. Thank you for your patience.
Omega Systems would like to inform our customers that you may be experiencing an inability to access online resources protected by Let's Encrypt / R3 certificates. Let's Encrypt is widely used by a number of web sites for encryption. At the moment, we are at the mercy of the firewall vendors to update their systems. This is effecting several firewall vendors. We are diligently monitoring and will keep you updated as we find out more.