If you’re on Windows, quote escaping can be weird. Try:
```
curl -X POST https://example.com/api -d "{\"key\":\"value\"}" -H "Content-Type: application/json"
```
Also, check if the API requires HTTPS or a specific user-agent.
```
curl -X POST https://example.com/api -d "{\"key\":\"value\"}" -H "Content-Type: application/json"
```
Also, check if the API requires HTTPS or a specific user-agent.
