According to Euler's formula, think about a polyhedron with 10 faces, 30 edges and 20 vertices?

According to Euler's formula, think about a polyhedron with 10 faces, 30 edges and 20 vertices?

Euler theorem: vertex + number of faces - number of edges = 2
Substituting into the formula, we get 20 + 10-30 = 0, which is not true
So, there's no polyhedron