This is how it happen

Lunch casually and randomly find a " quick service " Chinese restaurant in the ally nearby She Ta : where I print my workbook for Saigon .
I order a " stew rib " set : it come with side dishes and soup - looks great and pricing at 200
There is something wrong with my first bite to the rib - I tasted the sore which don't come as a flower but a rotten food , I split it out gently.
Then I approach the counter quietly and told the service man " the dish have some problem " he immediately take my rib away and send the menu for me to pick the replacement .
I can't - so I told him that I will eat my side dishes and pay the full - no worry
And I took a mouth wash at the water drain at the restroom before consume my dinner .
I finish all my remaining lunch . I saw owner ( or manger) stand behind the counter - I walk up and take 200 from my wallet : the owner said " I am sorry for he ignorance , the meal is on the house , please do come back "
My reply : no , you should at least take the cost , so I left 100 to the table and told him I will be back .
There's another 3 guests in the restaurant, they aware something is happen but nothing burst out .
This is what we can do : don't give hard time to people even you are standing on the ground call " REASON "


Roger