Look at the 2 attachments. Not sure why, but when I select a dotted rest, sometime the enter dotted rest is selected and sometime only the rest without the dot.
I’d need to see the project in question to know for sure, but I expect what’s going on here is that one of the rests is a real or explicit rest, and one of them is an implicit rest that Dorico has drawn to fill in the gaps between notes in a voice.