The dhikr prescribed after the taslim of the prayer: is it specific to the obligatory prayer, or does it also apply to the voluntary prayer?

The questioner:
He says: Honorable Shaykh, may Allah grant you success, is the dhikr prescribed after the taslim of the prayer specific to the obligatory prayer, or does it also apply to the voluntary prayer?

The Shaykh:
The prescribed dhikr is specific to the obligatory prayer. As for the voluntary prayer, one remembers Allah without being restricted to a specific type of dhikr. As for the obligatory prayer, one is restricted to the prescribed dhikr. Yes.

The questioner:
And is it permissible for him to say "I seek forgiveness from Allah" three times after the voluntary prayer consistently?

The Shaykh:
He is not required to do this, because this is only after the obligatory prayer. It is not required to do this and make it a habit after the voluntary prayer, but if he says it some of the times, there is nothing wrong with it. Yes.