Is it bad to use soap on the vagina area?

Yes: Soap in the vagina typically is going to burn or sting. There is nothing to clean in the vagina as the vagina has mechanisms (discharge) for cleansing itself. The outside of the vagina, the vulva, has sweat glands that produce a sebaceous (cheesy) material. And these glands can produce odor and oil that you may want to cleanse. The vulva can be washed with a non-irritating gentle soap.

Great question: You actually don't need to place any soap in the vagina to clean it. Clean external genitalia with soap. It is best not to put soap in your vagina. Take care.