Hello gogollny,
Well, I think you can’t return the software back to Steinberg, as they don’t have this practice.
You can try to sell it through FaceBook (there are groups for selling musical things), or on Ebay, etc.
Personally I would advise you to keep your copy of Dorico and give it a chance. Many improvements and
new features are about to come. Currently it’s much more intuitive than Sibelius and Finale…
Personally I came to Dorico from Overture 5 and Sibelius one month and 3 weeks ago… Still I’m thinking
that Overture is the most intuitive scoring software and it was very hard decision for me, but the app has
some problems due to wrong update politics of the developer, and I didn’t want to be a constant beta tester.
This is how I moved to Dorico… and I like it, despite that isn’t as intuitive as could be…
The decision is yours, but think once again before taking it! 
Best regards,
Thurisaz