Apex Automobiles - Improper Invoice

Recently, on **th of January **** I have bought an Okinawa Electric Scooter from Apex Automobiles,Tinsukia, Assam a authorized dealer of Okinawa scooters. While purchasing the scooter they furnished an extra Tax Invoice in the name of Accessories (Without mentioning the name of the particulars) of an amount of Rs. ****.** INR, after adding **% GST the amount was rounded to Rs. ****.** INR. My complaints are mentioned below..
*. They didn't assembled any accessories accept the rear view looking glass and a floor mat. If these are the accessories they are charging for, then they should name the accessories along with individual MRP of each item in the Tax Invoice. Which is not done by them.
*. As i noticed this i immediately asked them to provide me the detailed individual particulars of accessories that they are charging for but they denied to do so. After asking them several times on purchasing date they agreed to provide me the bill along with all the particulars and asked me to collect the same the next day. When i approached to them the next day they provide me the same bill named Accessories (without mentioning the particulars). On **th of January when i continuously asked them to provide me the appropriate invoice, they treated me so badly and challenged me they will not provide me the particulars in any condition.
It feels really bad and frustrating by the behavior of the dealer authorities. I have never experienced in my life a tax Invoice without the price of individual item. I didn't understand whats the problem with the company or the dealer to provide the price of individual item. Its one type of cheating and completely unfair with the consumers.