What is the way to get rid of remembering pornographic films during sleep, after repentance and cessation of watching them?

If you have repented with a complete fulfillment of its conditions, then you have done what is required of you, and your repentance is accepted, God willing. As for what you imagine at bedtime, there is no sin in it, because the pen is lifted from the sleeper until he awakens. To remedy this, increase your acts of obedience, especially remembrance (dhikr) and supplication (du'a), and you may benefit from consulting specialists.