How can I fix Threads app not responding on my iPhone?

Hi folks. When I try opening the Threads app—either directly from the app or via Instagram—I just get an error message saying “Error-Please check your Internet connection and try again”

Internet connection is absolutely fine and I have tried deleting the app, restarting my iPhone and reinstalling the app, but still the problem persists!

Any help would be greatly appreciated.

Many thanks!

Steve

[Re-Titled by Moderator]

Original Title: Threads app will not open