Disturbing lack of customer service

I walked in to the Bluff branch of Builders at 16:45 on Friday, 12 February 2021, to have my pool water tested. The first thing the pool guy did was point at the watch on the wall. Confused, I inquired what he was trying to say and told me that I was late and that whether or not he can assist me would depend on the pool testing machine. The last of the testing capsules was used and he had to re-load with a fresh spindle. The test was completed in less than 5 minutes and during that time, he repeatedly gestured to his watch to another customer as well, telling her that she should hurry up as the store is closed... The service thereafter was poor, as it was clear that he was upset. When I finally chose the items I needed, paid for my purchases and walked out the store around 16:57, I noticed that this employee was already at the far side of the parking area walking out the gate. It was clear that he was rushing the few remaining customers so that he could leave 5 minutes early. This was a very unpleasant shopping experience indeed.

Please advise what steps will be taken to prevent a recurrence of this behavior?

Thanks