There are no reliable AI detection services. At best they can reliably detect output from popular chatbots running with their default prompts. Beyond that reliability deteriorates rapidly so they either err on the side of many false positives, or on the side of many false negatives.

There's already been several scandals where students were accused of AI use on the basis of these services and successfully fought back.

I've tested some of those services and they weren't very reliable.

If such a thing did exist, it would exist only until people started training models to hide from it.

Negative feedback is the original "all you need."