Broken link when I try install application blink

Hi! I need help. I installed Flatpak on my Ubuntu 18.04 and after rebooting the system, I tried to run the command: flatpak install flathub com.icanblink.blink
I got an answer: Error searching remote flathub: Can’t find ref com.icanblink.blink

I tried to reproduce but it’s working for me:

$ flatpak install flathub com.icanblink.blink
Looking for matches…
Required runtime for com.icanblink.blink/x86_64/stable (runtime/org.kde.Platform/x86_64/5.14) found in remote flathub
Do you want to install it? [Y/n]:

Can you install other packages from Flathub? Perhaps it was a temporary connection issue?

Which architecture (CPU) do you run this? Also which version of flatpak?