Is it a condition for the acceptance of repentance to strive to remove images and video clips—displayed in cathedrals—that were mistakenly captured, and then the phone on which these materials were stored was stolen?

As for entering churches, many scholars have permitted it. As for the forbidden things on the stolen mobile phone, if it is highly probable that you cannot retrieve it, then there is nothing upon you, and it is hoped that your repentance will expunge the sin of others benefiting from this SIM card. For whoever repents from a sin whose effect remains, he will not be held accountable. It is advised to disregard whispers (waswas) especially concerning disbelief (kufr), because giving in to them leads to great evil.