There was a network issue connecting to Leo, check your connection and try again.
I do not use Leo often, I noticed it several days ago, still not working whatever I do, I tried changing DNS, using VPN, creating new profile, nothing fixes it.
I use Brave for Android 12, stable 1.66.115 and also nightly 1.68.44. Same issue on both.
Also Brave 1.66.115 flatpak version on Fedora Silverblue 40, same issue.