Why my earphone is unsupported while it works well for first couple of minutes?

When I connect my earphone on my Iphone X, it works pretty well for about 5-10 minutes. Then, suddenly a message arrives, "This accessory isn't supported by your iphone". And, my earphone stops working. After replugging in, this happens like same.

If my earphone is unsupported, then how it is working for first couple of minutes???