Question

why does positive charge on benzene ring do not resonate explain

Answer 1

The reason it won't is because it is not in the p-orbitals which are conjugated together and very stable in their configuration. So think of the hydrogen atoms on the outside as one of those being lost.

This is similar to why neutral Pyridine can accept a hydrogen and act as a base but neutral Pyrrole can't gain a hydrogen on its nitrogen since its lone pair is tied up in the resonance of the p-orbitals.