Not the best burger spot

Worst service I have had at a Bossa. We ordered 3 burgers. Supposedly "The Best in Town". The one of the burgers that arrived at the table was the wrong one and had mushrooms. When we complained the waiter asked "Are you allergic to mushrooms or should I bring another?" We asked for the correct burger and waited 20 minutes while burgers were served to other tables and we finished the burgers that we already had. I complained to the manager who said she would check on the replacement burger. 5 minutes later the burger came out and it was with a single patty where it was meant to be a double patty. I complained again and after a further 5 minutes the burger arrived. However, clearly not the "Best burger in town." Will be hard pressed to come to this Bossa again.