Blinker/Flashers (2002)

Hey everyone, I am new to the forum and a novice about car repairs. My blinkers and flashers will work intermittently while driving. My car went into the shop for an oil change and I asked my mechanic to check the blinkers/flashers. He said he couldn't fix them because he couldn't replicate the problem.

I am wondering if anyone on the forum has had the same issue and how they got it fixed. I hate driving around with signals that don't always work.

Thank you everyone!