GST on MRP

I ordered a bottle of pepsi, worth Rs 38 (MRP). The person in-charge gave me a bill of the beverage, Amount- 38.10 plus GST 5%, even though the MRP printed on the bottle is 38. I would like you to send me the response/result of my complaint on my email ID because I have filed complaints beforehand, but did not get a response on my mail ID