“Don’t Import Suspected Duplicates”

[Francis23984836g3hw]

I can't import some photos.  Lightroom says these were already imported.  I can't find the Don’t Import Suspected Duplicates button to uncheck it.  Thanks

[selondon]

In the cloud based Lightroom there isn't the option. 

Hopefully, you'll get more advice but trying amending the photos is some way, so they are different sizes in Mb or time stamp.