I have a plant tagged as Dipladenia.It does look like it from your photo but it has a vine that started growing just recently and it is now about 3 feet TALL(that is growing up and not hanging down)Is it Dipladenia?
Certified GKH Gardening Expert
Both plants will vine and have similar growth patterns.
Dipladenia and Mandevilla are sometimes miss tagged.
Here is an article to help you make the identification.