Can't log in to newly installed AC Forums app

[Netherthorpe]

I've just installed the AC Forums app in my (Android 6) phone, but am unable to log in to it ('Incorrect user name or password', in spite of 3 very careful attempts so far).
I searched here a bit, and gather that I should see options including 'Google sign-in' (which I use), but I can't find them. I'm entering my forum screen name and Google password, which works when coming here with my browser (my default one's Chrome). At least, I think it must have done (I sign in automatically via browser - would rather not risk logging out & in to find out!).
Am I just being dim?

 

[Stevenmc8602]

I've seen other ppl say this but I didn't have any issue...

Maybe it's a bug

 

[Netherthorpe]

Thought it might just be my fluctuating internet signal, but the problem still persists when it's having faster periods (and at all times of day, apart from dead of night British time).

I'd insert a screenshot of what I'm seeing, but I tried this app because it was recommended in the sticky about inserting photos in postings here, which I was re-reading because the photo uploading icon above the composition area has stopped working for me!

Should have mentioned, re using browser, that it's also from my phone (my computers are out of action at the moment). I use Chrome by default (using Firefox doesn't make any difference, and the icon method was working fine for me about a week ago, in Chrome).
At the same time, I've been inserting photos in posts on a different website with the same icon, with no problem (but maybe I'm getting too far off topic!).