Cs0106 The modifier 'private' is not valid for this item How can I resolve this

Unity Engine
,
1

I tried to build game but this line show error

private IEnumerator System.Collections.IEnumerable.GetEnumerator()
{
return (IEnumerator)null;
}

2

Like the error states, private is not valid for that line.

An explicitly implemented interface member should not have an accessibility modifier. Remove it.

3

Which line need to removed

4

No line needs to be removed. Remove the private access modifier.

5

An IEnumerable that returns null is pretty pointless.
Are you sure you want to implement IEnumerable?