I was at the gas station, in line waiting for one of the three gas pumps to be available. I put my car in reverse to back up and pull around another car in order to go to the open pump in front. When my car was in reverse motion, I stepped on the brake pedal, but the car did not stop. I stepped on the brake pedal numerous times, but the brake did not function. My car backed into the front of the car in line behind me damaging both vehicles. The automatic emergency braking system did not activate, and there was no rear collision warning sound or message. I switched my car from Reverse into Park to stop its movement, but it was too late to avoid the collision. I had a passenger in my car who corroborates this description. Fortunately there were no pedestrians behind my car, so the only damage was to the vehicles. My vehicle has not been inspected by anyone since the accident, but will be soon. I have owned this car since April 2021 and previously had a few similar situations when moving in the forward direction. Previously, the brake problem occurred while moving forward at very low speed pulling into parking places. The brake failed to activate, and I had to throw the car into Park to stop it, but this was the first time I had experienced this problem traveling in reverse. When this situation occurs, I am pressing on the brake pedal, but the car is not stopping and the brake pedal seems to go to the floor. On March 5, 2025 I took the car to a Lexus dealer and