How can one trust an untrained pharmacy assistant

Been to the Clicks pharmacy Riverside boulevard Vanderbijlpark this morning just to buy a 15ml Saffer blue, eyedrops. Went to counter number 1 and asked for the product, the pharmacy assistant looked at me as if I was asking for something out of the world with a question mark on his face, I repeated my self and he was even more lost. He then proceeded to reply by saying "let me look at your profile to see if I can pickup what you want". Being frustrated I again aked for the same thing and the lady next to him said, the customer wants Saffer blue. He then turned around picked a 10ml bottle. Clearly he didn't understood 15ml. I questioned his ability to serve customers as it doesn't appear to be so. He rep**** "I'm a professional, I can't hear what people are saying behind their masks. " I then left the counter because how can you trust to be served at a pharmacy by someone who is clearly not trained to be there.