Ninja for does not process with HTTP:// is inserted with a link

Hi
I am trying to diagnose a problem where a form does not complete, the page just reloads without an acctions or posting of the form taking place.

I have narrowed this down to a problem with a field that is required which takes a url which if the indervidual cut and pastes, will most likely include the HTTP:// part, and its when this is in the field that the post fails, but when say ‘www.google.co.uk’ is used on its own, it works, but ‘https://www.google.co.uk’ does not.

I have disabled all pluggins to test including security ones and this did not change the problem.

https://www.spelthornebusinessforum.uk/request-to-add-your-events-here/

https://www.ads-software.com/plugins/ninja-forms/