For two things to be said to be the same, they have to be different, or there wouldn’t be two things to be said to be the same.
Even if we refer to things that seemingly are the same in two different ways, for example equilateral triangles and equiangular triangles, and say “equiangular triangles are the same as equilateral triangles” there must be a difference that can be referred to, because someone could know of a triangle that it is equilateral and not that it is equiangular for instance, and therefore one triangle has the property “known to be eqilateral” and the other the property “not known to be equilateral”.
If we say that two things are actually different though they must in some sense be the same. So for example Heracleitus says we cannot step in the same river twice. But he is able to identify something as a river in order to say of it that it is different from moment to moment. It’s different from talking about a shoe one moment and a river the next.
So it’s a problem!