openpharmacophore.molecular_systems.exceptions.DifferentNumAtomsError: Ligand contains 27 atoms, while smiles contains 40 atoms

[JeongSooNa]

I get this error in python, using openpharmacophore modules

raise DifferentNumAtomsError( openpharmacophore.molecular_systems.exceptions.DifferentNumAtomsError: Ligand contains 27 atoms, while smiles contains 40 atoms

Is there any specific formats in pdb and ligand, in openpharmacophore package?
the smiles is "CN(C)CCCNc1nc2cc(c(cc2c(n1)NC3CCN(CC3)Cc4ccccc4)OC)OCCCCCN" and I get printed 27 in print(ligand.n_atoms)