They say sorry and then do the same thing again
ADHD child behaviour
The apology and the repeat come from two different brain systems. The reflective one that produced the sorry is slower and weaker than the impulsive one that produced the behaviour, so your child meant the apology and still could not stop the impulse. The remorse is real, and eroding trust misreads it. Stop asking whether they are sorry and ask which skill is missing, then build that skill.
What to do right now
They meant the apology when they said it. The next time the situation arose, the apology was in long-term memory and the impulse was in the present. The impulse won. They are not lying when they say sorry. They are not choosing to repeat it. The gap between intention and action is where ADHD lives. Teach the skill, not the remorse. They already have the remorse.
What your brain just did
Your body
They apologised sincerely. They repeated the behaviour. Your trust in their apologies is eroding.
Your brain
The apology used reflective cognition. The repeated behaviour used impulsive action. These are two different brain systems. The reflective system that produced the apology is slower and weaker than the impulsive system that produced the behaviour. They meant the sorry. They also could not stop the impulse.
What this did
Shift from 'are they sorry' to 'what skill are they missing.' The apology shows they understand. The repetition shows they cannot yet execute. Build the execution skill.