White smoke is usually normal, yeah, this one's common. It's steam or oil heating up.
Fix: First, unplug the unit and let it cool. Pull the basket out to speed this up. Once cool, clean the basket and the inside of the air fryer thoroughly. Grease or oil buildup under the crisper plate is a prime cause. Cooking greasy foods will cause oil to collect there, which produces smoke. Handle the basket with care when it's hot.
If that didn't work: If you see dark smoke, that's different. Immediately unplug the air fryer. Dark smoke means food is burning or there's a circuit problem. Wait for the smoke to clear before pulling the basket out. If the cause wasn't burnt food, you need to contact Cosori support.
Heads up: Some white smoke or steam during first use is normal. Just make sure you're not overfilling with oily food and you clean regularly.