Welcome to our community and thanks for posting. Really sorry to hear that your 1471 feature has an error code and has just stopped working.
It very strange how both you and your mother have been affected by the same issue and you live in the same street? As you have both been affected by this it may be an area fault which is affecting you which has not yet been reported.
Looking remotely from our end we cannot see any issues which may be causing this error so we will need to get this looked in to for you.
What is the message when you get when you call 1471?
Thanks so much for popping back @Loupomm and confirming the error message.
It's certainly not one that we have heard before - we have once again checked the exchange on your line and no errors are showing this end adn we can't see any issues with it so far. Due to this, we have removed and re-added the feature. Can you please recheck for us and keep us posted.