As per this counterspell dnd 5e you can attempt to be interrupting a creature in a process of casting a particular spell. Suppose, if the creature is able to casting the spell of 3rd level or else lower than it, its spell fails and even it does not have any kind of effect.
However if it is casting a spell of 4th level or even higher level, then it make an ability check using your spellcasting ability. Actually, the DC would be equal to 10 + the spell’s level. Particularly on a success and the creature’s spell would fail and also has no effects.
Did you check charm person 5e spell ?
At Higher Levels:
Being this counterspell 5e, when you do cast this spell by using the spell slot of 4th level or else more than this 4th level, the interrupted spell has no effects when if its level is less than or else equal to the level of a spell slot which has used by you.
Attributes Of Counterspell DnD 5E Spell
|Casting Time||1 reaction, which you take when you see a creature within 60 feet of you casting a spell|
|Classes||Sorcerer, Warlock, Wizard|
|Target||A creature in the process of casting a spell|