I cannot see any warning when testing the code:
(I’m using Chrome.)
Perhaps “required” is missing from "input
This is because nothing is going wrong. Setting the min/ max in the tag only works if the input changes with those arrow buttons. Direct input on the input field itself is still allowed.
Note: Al tho it visual allows inputs above and beneath the min and max. I do not know if the input will return these values or if it will take the max/min value you have set. You should test this.