searches returning no records, when there are

Hi there.
So, in using geodirectory in the wild, we’ve come across a little problem.

Our directory is mostly UK (with a few listings in Ireland, the Netherlands and 1 in Turkey), When someone uses the search feature something very odd is happening for those places where there is a USA place with the same name.

If, for example, I enter Brighton into the search box and hit enter (without waiting for it to drag up options such as Brighton and Hove, East Sussex from my database). It comes back with a “No Records Found” notice, and the map is centered on Brighton, Colorado?!?! (see attachment)

Do you have any ideas for me? this is from my site users, who keep complaining that they’re listings aren’t there.

Thanks!
lana
(ps: using WordPress 4.8.1, and GD Version 1.6.23, and advanced search Version 1.4.91 )