2000 Toyota Camry sometimes gas pedal cannot be pushed down

This happens a few years now. It doesnot happen a lot but it is bothersome. It usually happens when I stopped on a red light and then when the green light is on I push the gas pedal but could not push down. I have to release and push again for a few times and all the sudden the pedal can be pushed down and the car can go now. Not that bad but I would like to fix it by myself if it is an easy fix.

To me it feels like an axle along with the gas pedal is stuck or need a bit oil. But I don't understand the whole system。