Answer for System Failure: For GSTIN
System failure is an error which may occur due to heavy site load or multi-browser login.
Refreshing the browser may be a solution, but I am not sure.
Also It is always advisable to write to helpdesk, which you already did.
I suggest you to try some time later or with other computer. Although helpdesk is the ultimate authority to respond.
I also request you to share the answer received from helpdesk for others.