Use a short extension. A few bucks on AliexpressDid you ever find a better adapter? My iPower Elite does not fit snug either. The iPower connector is longer than the stock M17 power adapter which means it bottoms out inside the plug and not on the outer housing of the plug. This makes it 'loose' even though it's connecting power just fine. None of the provided adapters were the correct length. I don't think it's a huge deal because it's still connecting just fine internally, it's just annoying that it can move around because the tip is too long.
...or even better, this adapter