the security certificate for shop.udoo.org appears to have expired (29/12/2019, 09:56:21) which is a little odd for a Lets encrypt certificate setup. someone needs to check the servers auto certificate renew setup, or fix it manually
Thank you for letting us know. We've notified the company that built the website and they have resolved the issue already.
On this topic: udooer@udoo:~$ sudo apt-key list | grep -A 1 expired [sudo] password for udooer: pub 2048R/71F0E740 2015-07-22 [expired: 2020-07-20] uid UDOO Team <social@udoo.org> could you please renew this key? Cheers!