Hi,
This is already fixed and ready for the next update.
To fix it in your site you just have to change a line of code in the file at plugins/swift-framework/includes/page-builder/assets/js/page-builder.js
Find this line 2144 in v1.7
'click', '.column_clone', function( e ) {
and replace it by this one.
'click', '.controls_right .column_clone', function( e ) {
After that clear the browser cache and try again, let us know if you made it and if you need further help with this.
Happy New Year
-Rui