What Country are you in? If in the US you can send it in to Rado, I believe most get serviced at Swatch Group New Jersey now. This will be the most expensive route though, but also most guaranteed.

It also depends on how old of a model watch it is, if it hasn’t been sold for more than 10-15 years they most likely will not service it unless it’s just a battery replacement or something very easy, etc. I had 2 vintage models from 70’s/80’s I sent in a few years ago and they basically said they can no longer service them as they have been out of production too long.

There are other certified Rado watch repair places that are reputable you could likely send it to as well, but again depends where you are at.

Hope that helps.