اَللَّهُمَّ إِنِّي أَعُوْذُ بِكَ أَنْ أُشْرِكَ بِكَ وَأَنَا أَعْلَمُ، وَأَسْتَغْفِرُكَ لِمَا لَا أَعْلَمُ

Allaahumma 'innee 'a'oodhu bika 'an 'ushrika bika wa 'anaa 'a'lamu, wa 'astaghfiruka limaa laa 'a'lamu

O Allah, I seek refuge in You lest I associate anything with You knowingly, and I seek Your forgiveness for what I know not.

Reference: Sahih. Adabul Mufrad: 716