Can't use coupon in admin panel when edit order

Hi, I'm on 2.3.0.2
For example I set a coupon for free shipping, and client didn't apply it, so I have to apply it in admin panel.

But when I edit it, and try to apply coupon, system keep report code is invalid or exceeded something like that.

But the exact same code is working in front end, and I also tried set a new code but it doesn't work in backside as well...