What should you do if you recall a sin that you felt was an act of mockery, despite your repentance from it, but you do not feel remorse?

We advise you to turn away from whisperings (waswas) and to have a good opinion of Allah, trusting that He has accepted your repentance, citing the noble verse: "Say, 'O My servants who have transgressed against themselves [by sinning], do not despair of the mercy of Allah. Indeed, Allah forgives all sins. Indeed, it is He who is the Forgiving, the Merciful.'" (Quran 39:53). And likewise, the Hadeeth Qudsi: "O son of Adam, so long as you supplicate Me and hope in Me, I forgive you for what you have done, and I do not mind..." What is required upon remembering a sin from which you have repented is that it grieves you, for remorse is repentance. And whoever is pleased by his good deed and grieved by his bad deed, that is the believer. It appears from your words that your repentance is sincere and that you do not find pleasure in recalling your past sins.