How to do after the thread insert have been installed , the plug guage detect the fixed  gauges doesn't  stop work ?

How to do after the thread insert have been installed ,the plug guage detect the fixed gauges doesn't stop work?

(1)The precision grade of plug guage and thread insert are not match :the order should be according to the grades of plug guage's precision to choose the  same class thread insert .
(2)The plug guage is improper,as with the British 55 ° tooth angle plug type detect Unified threads (UN series) 60 ° angle of tooth-type thread insert:Replaced with the same series of plug guage.
(3)The drill is too big: change a drill in suitable diameter instead of it.