Shortcode subscription form -> Fields are far apart

Hi, thanks for the great plugin!

I just recently switched from another plugin to Knews. I now want to add subscription forms to my pages. I have used the shortcode (both the short one and the longer one) and have one problem:

The fiels are very far apart. As if spacers were put in between. I have tried a couple of things to change it, but so far I have not found the solution. Do you have any suggestions how to change this or where to look for the problem?

Sorry for my vague question, any help would be much appreciated!

Thanks, Leonie

https://wordpress.org/plugins/knews/