Biryani Blues — biryani blues - service charge in addition to gst

Address:

Gautam Buddh Nagar, Uttar Pradesh, 201301

I had dine in biryani blues restaurant in sector 50, noida. Before billing, i said i do not want to pay service charge. But restaurant manager said it is mandatory to pay service charge in addition to 18% gst as per company's policy. I had an argument with that it is illegal to charge like this. But he forced me to pay service charge of 5% in addition to gst of 18%.