Can't export to Youtube (Windows)

I'm having an issue when trying to publish a video on Youtube. I've signed into my account countless times and as you can see from the picture, in the channel selection tab I'm signed in before I click export.

However, once I click export and it goes through the rendering this pops up. If I try to export again I have to sign back into Youtube. Also if I change any export settings after signing in it also makes me sign in again. 

I know it's completing the rending as the rendered videos appear in the folder as if I'd just exported them to my computer, though they come out with _YouTube in the title.

Just to clarify I'm on a Windows PC and I can export my videos perfectly fine to my computer and then upload them to Youtube outside of Premiere Pro, just the direct export to youtube isn't working.

A few things I have tried are as follows: 

1. Closing Premiere Pro while signed into Youtube and then opening the app again.
2. Exiting Google Chrome and reopening after deleting my cookies & cache.
3. Restarting the computer.
4. Restarting the computer after deleting my media cache on Premiere Pro.
5. Fresh install of Premiere Pro.

Any help would be much appreciated and any guidance on how I can report the issue to Adobe as a bug if it's even worth doing.

Many Thanks,

Kirsty