Originally Posted by
plunet
Double double check all the data matches what you think it should be, assuming the ETA confirmation email shows all the data on what the ETA was based.
There's an option to do a WeChat with UKVI on this page if you want to try to query what's gone wrong.
https://www.gov.uk/contact-ukvi-insi...horisation-eta
Great advice - thank you. Chatted via WebChat, the issue was that I did not know that I need to input the letter before the passport number in the system (I normally never deal with Austrian passports).