External links not working

Hi All,

I have many wordpress websites and this is the first time I have encountered this problem.

None of my outside links work ie paypal buttons and advertising banners.

here is my site https://twisted-uk.co.uk/

As a test I went back to a previously used theme for a second and the links all worked…So it is clearly something to do with my current theme…Any idea how to fix this or do I need to just use a different theme? ??

The current theme (which is not working) is RestImpo

I’m completely baffled by this. Any help would be muchly appreciated.
Many Thanks
Donna