“GST e-Invoice Web portal and APIs on Production environment will be down due to urgent maintenance activities during 11/12/2020 (Friday) 11:00 PM to 12/12/2020 (Saturday) 01:00 AM. Taxpayers are advised to plan and re-align their IRN generation activity accordingly; inconvenience caused is regretted.”
However, Please note that E Way Bill operations on the E Way Bill System are not affected.
Source from: https://einv-apisandbox.nic.in/