1. Do as the error message says and Reseat the AC power cable, while you're at it, reseat the battery as well.
2. If your battery is still 10% full, you could update the BIOS of the computer.
3. Press F2 and check the Battery Health and Battery Info. You will have and idea whether the battery or the AC adapter is the one causing this problem.
4. Test using a known good AC adapter and Battery.
5. If after trying a different AC adapter and Battery and it's still showing this message or if it's still not charging, Tech supports usual nest step would be to send a technician to replace your motherboard.
6. For Studio XPS 16 and Studio XPS 1340, and upgrade from 95W to 130W AC adapter has been rolled out by dell because power requirements for these systems seems to be more than they originally expected.