Facebook Messenger not working on iPad Pro

I have a new iPad Pro generation 5 - everything has set up easily with the exception of Facebook messenger which refuses to load. I have tried uninstalling the app, turning of the i

pad, rebooting and reinstalling, but always with the same result - I see the Meta icon briefly flash onto the screen and then I’m left with a white screen with an never-ending spinning loading icon. Can any help please.

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