Kamado won’t cool down

Hi, I just got a Kamado and did my first cook at the weekend. I filled the basket with lump wood and cooked burgers, sausages etc - nothing that took too long. I closed it up to kill the heat but although it cooled a lot it didn’t entirely go out. I noticed it a couple hours later and double checked to make sure nothing was open. I lit it back up about 24 hours later and it was still slightly warm. I got through a whole large bag of lump with just those two short cooks. Any suggestions about what might be wrong?