Upvote:3
The information [...] was not reliable means that they are not sure you are a genuine tourist. They are afraid you want to work illegally and overstay. So you have to ask yourself, is it a deficiency in your submitted documents that led to the refusal, or are your current conditions such that you would want to stay in Germany if you could?
If you have very good reasons to return and they denied your application anyway, there may be something wrong with the documentation only.
If that is not the case, an appeal probably won't help.