Nothing went wrong per se, it’s more likely that no one told you about the expectations of college level writing or you were too nervous at orientation and weren’t listening. Whatever it was, here you are now wondering how to write an essay that’s acceptable in university.
The key to a good descriptive essay is to really dig into the five senses as they relate to the subject of your essay. For example, if your essay is about a trek in the forest you’d focus on the senses of touch, smell, hearing, and sight, maybe not so much on taste. A well crafted descriptive essay will allow you to share a picture of something as vividly and as genuinely you can and to transport your reader into experience where they feel that they are actually seeing, hearing or experiencing it themselves.
There are a number of services out there that promise to write your essay for you as a professional service. They promise that they are "100% Plagiarism Free," but all that means is that they will write your essay for you (rather than simply find something online), but it's still plagiarism. You know why? Plagiarism simply means that you are passing off another author's writing as your own, and is considered academic dishonesty.