Manager's finger in my food!

I ordered kingklip and was given basa!! When I complained about it the manager arrives with excuses without allowing me to speak. He then says the supplier has been giving them the kingklip that is slimy like basa!! He then sticks his finger into my plate and points into it less than a centimetre above my meal! I literally had to move the plate away! Disgusting seems unfitting! I was insulted! When has kingklip been slimy and thinner than hake?! He then walks away without even trying to appease me!! The worst service and most disgusting experience I have ever encountered!!