Great job on delivering the SD at the correct time.
Giving corrective feedback is always difficult but if you are using an FR1 schedule of reinforcement, this needs to be provided on each trial, contingent on the behaviour within 0-3 seconds. This will help the acquisition rate of your learner.
Let’s practice now. I will model the skill and ask you to do this in role play and then we will follow up in our next supervision session with an in-vivo observation again.