I know that, but since I make money only from donations without giving anything in return of the money I am considered non commercial. For now I decided to use NLLB instead of Opus because it has good quality and is a single model for all languages (so I didn't have to implement the download management logic for the various languages and I was able to make the app faster), but it is a temporary solution, I will certainly replace NLLB in the future, either with OpusMt Big or with other models with a less restrictive license.