The ruling on leaving an obligatory part of the prayer with a long or short interval

Question:
He says: Honorable Shaykh, may Allah grant you success, if one leaves an obligatory part of the prayer and the interval is short, what is the ruling? And if the interval is long, what is its ruling?

Answer:
If one leaves an obligatory part of the prayer by mistake, he performs the prostration for forgetfulness. If he has already said the closing salam, he performs the prostration after the salam, unless his ablution is broken after the salam or the interval is long, in which case the prostration for forgetfulness is dropped from him. Yes.