Head to
https://portal.zen.co.uk/ and sign in
Click My Services > Broadband and SDSL
Click View Technical Details
NOTE: I've had an active FTTP connection over Openreach Fibre since 2018 so it might be that they don't offer the same level of technical detail (OR doesn't need a VLAN ID configured for example) but I'd check there that you've got the userID and password correct and it should hopefully also give you any other details you need.
Good luck.
Virgin (ADSL) => Namesco => Newnet => O2 => Plusnet => Zen => Newnet => Zen => Freeola => Vivaciti (using O2 Wholesale DSL) => Xilo (C&W Wholesale) => Xilo (O2 Wholesale) => Xilo (TT Wholesale due to O2 Wholesale closure) => Zen LLU =>> ZeN FTTP (Openreach 300 Mbps down, 47 Mbps up)
Router: Fritzbox 7530
Note: I don't lay turf for anyone. astro or otherwise, all views and opinions expressed are my own based on experience.