FYI the Camara Municipal for Lisbon is currently closed due to the pandemic. UK residents (or any EU citizen) requiring a Registration Certificate (Certificado de Registo) are being instructed to fill out the form on this website: https://cutt.ly/crue
A Portuguese government institution wants people to fill out a form on a site in Libya (.ly)? I think that warrants additional scrutiny.
Itās not a website in Libya, the url is just a short url generated by a service like tinyurl or similar. It takes you to a microsoft form with a really long id parameter that would be impossible to type by hand.