Cup noodles should not be microwaved since they are not safe. The styrofoam cup in which the noodles are packaged is not intended for microwave usage. The possible risks are twofold: the first is the breaking, leaking, or deteriorating of the cup, which might result in a dangerous chemical release into the noodles; and the second is the deterioration of the cup.
Why can’t you microwave noodles?
It is not possible to microwave a cup of noodles due to the risk of overheating. If the foam melts into the dish, it has the potential to alter its flavor and the taste of the noodles. It is also risky for people who consume the noodles since the melted foam might enter their digestive tract and cause problems.