Hello everyone, newbie here, so thank you for your patience.
This weekend, I've been having the reverse problem as the OG poster: I am blocked from booking a BER-VIE-LHR route. I have tried both the OS and LH websites on different browsers (Safari, Firefox, Chrome), as well as third party searches on Google Flights, Kayak, and Expedia.

Would anyone have an updated fallback LH website link? If not, I'll try their phone customer service on Monday.

Thank you for any help or insight you may have on this!