Browsing issue after disconnecting a per-app vpn session

We have certain in-house applications allowed to be accessed from iOS devices using per-app vpn functionality (with split tunneling disabled) . Initially, users get connected to corporate wireless and access such applications without issue, everything works smoothly. However, after get disconnected from VPN, browsing does not work with safari but it works fine with chrome. It is only happening on the corporate wireless network and not the same behavior on any other network like 3G or 4G etc.

Please share any of your experience, if any.