Sometimes when signing in by connecting an external wallet, users don't receive the popup to confirm the action in their wallet app or browser extension.
If on mobile, if your wallet app has an in-built browser, try visiting app.uranium.io via the in-built browser, which is known to be a more stable option.
If on desktop using a browser extension, please completely close your browser, and re-launch it. Then visit app.uranium.io and try again, ensuring you re-log into your wallet via the browser extension first.