HONDA 2 WHEELARS INDIA - Refused to provide a valid invoice

Respected Sir/Madam,
This is Rakesh Singha 'Address- Saheb Para, Parbelia Colliery, PS Neturia, District Purulia, WB ******(Current address)', I had been gone for my father's(Aditya Singha) bike(Honda Shine SP CB***) servicing(*nd free service) to my nearest Honda showroom which named "Maa Auto" Address- 'Sarbari, PS Neturia, District Purulia WB ******'. After service they charged me RS **/- for lubrication, oil, etc. on a simple white paper with signature & stamp, at the same time I am asking for a valid invoice copy to pay the balance but they refused, I was telling them that I have no problem to pay the balance but you should have provided a valid invoice copy for that, at that moment they said me that this is the way they are charged for their customers. They are continuing to harassing me mentally. One of their staff snatch my bike's key for stopping me to go home because I had told the manager that I would like to go nearest police station for a complaint against your unauthorized bill, they try to snatch the unauthorized bill which I have been collected from them also. Is this the fairway to deal with customers Sir! Shame on this type of person. That's why kindly request to you for stepping on these types of over dominant activities as early as possible and thank you for everything.
Dated: **/**/****