[Plugin: ByREV Gallery Pagination for WordPress] issue in v1.7.0 when going to update gallery

Hi I have v1.7.0 of the gallery and as i have used this gallery before on other sites, i felt i could again but with this version of wordpress i cannot when i go and add a image to the gallery by selecting a page in wordpress > edit > clicking on the big gallery rectangle with the camera photo in and on the top left next to delete it comes up with:

Are you sure you want to do this?

Please try again.

is there a fix for this as its somewhat frustrating.

thanks
graham

https://www.ads-software.com/extend/plugins/byrev-gallery-pagination-for-wordpress/