I visited your restaurant on date  and this letter is written to bring it to your notice about certain unacceptable behaviour from your end during my visit. I had booked an appointment at your restaurant for the purpose of client meeting along with goodwill lunch. We arrived at the restaurant well before the scheduled time to avoid any last moment confusion.
As we had the meeting first in our agenda, we informed the restaurant supervisor that we will be ordering the lunch once we are done with the meeting. After the meeting, I made a call to the restaurant supervisor to take our orders. He took our orders on time and promised to deliver within half an hour. In the meantime, we ordered drinks to kill the time.
Once we were done with the drinks it was almost past half an hour and the supervisor informed that it will take another half an hour to serve the food. We agreed on that and indulged in casual gossip. I reminded him after thirty minutes and he told it will take some time. I am very disappointed that we were served food after two and half hours of ordering. This is really pathetic as you people promise prompt services. My client was quite disappointed upon me on this kind of behaviour.
I would appreciate if you investigate this matter on priority. This kind of behaviour is really not acceptable and should not be repeated.
[Name of Sender]