VFS unstable site

We are unable to get help on rescheduling a visa extension meeting. The meeting needs to be rescheduled due to the fact that we are unsure if VFS will be open on the day of the meeting due to lockdown restrictions (4 May 2020).

When trying to reschedule the meeting on VFS's site, we get the following page with only a header saying:

"You have already taken an appointment. Please use reschedule, cancellation or retrieval for further process" - No options for rescheduling, cancelling or retrieval.

This needs to be resolved NOW, I'm not paying for ANOTHER booking.