What's going on?

I forgot to complete last week's Salvage Yard Robberies, however I finished all the preparations... and then the new week came, with new cars to rob, i go to the game and finish that rob, but i can't enter any cars, or my Salvage Yard workshop after i delivery the car to the Salvage Yard. Then i switch to new session and that car is now only worth $0, i can't even do the new car robbery mission, because it shows: in progress. Any ideas?