Cannot share dashboard

When I invite a colleague and click share it says that the dashboard has successfully been shared, but then you look on the 'shared with' tab and they are not listed.

This colleague was invited before and I cancelled their invite. I now want to re-invite them.

This has only happended since the autofill in the email address bar was introduced (I think - I've not seen the autofill until very recently).

The dashboard has custom visualisations, which I am having problems with when I try and load it in desktop as these were added online - but that's a seperate issue, just trying to think of things that might be related..

Thanks for any advice you can offer.

Alexis