F1 Visa approved but passport given back without stamping [closed]

The good news is that they found no reason not to grant your visa, so you can expect that you will ultimately get it. The bad news is that it has gone into administrative processing, so you will need to wait a while to get it. The official guidance is that most cases will be resolved within 60 days of the interview, and that you shouldn't make inquiries about it until that amount of time has passed.

The State Department has never said what administrative processing is, but Internet rumors (for what that's worth) tend to suggest that it involves a request to other agencies, made after they have your biometrics and sworn statements from the interview, to see if they have derogatory information about you that the State Department was unaware of. If there is no such information to be had you are good. Note that this is "normal", in that a certain fraction of all visa applications end up in administrative processing, and I have personally not heard of a case where the person in administrative processing did not ultimately get their visa. The State Department has also never said what triggers administrative processing. It might even be random or algorithmic selection having little to do with you personally.

In any case, you can expect to get your visa but you have no choice but to wait out the administrative processing delay, and you'll need to deal with any consequences of that since there is no way to hurry them up. Chalk it up to bad luck.