Is there any influence on the hair, if the coating on the ironing plate of the hair iron comes off?

If the coating on the ironing plate comes off, it may not smoothly slide and cause damage to the hair.

There is a defect in the iron I purchased at Amazon.

Seek assistance from the shop where you have made the purchase. If you have placed an order on Amazon, please check the shop you have made the order in Amazon. Please check the “seller” information from your Amazon purchase history and contact the seller.

Is MINI STRAIGHT IRON double ionic?

MINI STRAIGHT IRON is not double ionic.

I think that the MINI HAIR IRON STRAIGHT/CURL should be cooled down before placed back into the heat-resistant bag. How long will it take to be cooled down?

It takes 20 to 30 minutes for it to be entirely cool. Please make sure if it is cool enough to place into the heat-resistant pouch.