Giulia is correct about your first sentence. The second sentence is correct until the last word. It should be "the service I received" or "got." The third sentence is tricky because it is correct as a sentence. However, based on the other two sentences, it appears that you are trying to express your opinion of service received in the past. This sentence is in present tense. So, if you mean service received in the past it should be, "I am happy with the service you gave."