﴿ وَجَآءَ إِخْوَةُ يُوسُفَ فَدَخَلُوا۟ عَلَيْهِ فَعَرَفَهُمْ وَهُمْ لَهُۥ مُنكِرُونَ ﴾

“AND [after some years,] Joseph's brothers came [to Egypt] and presented themselves before him: and he knew them [at once], whereas they did not recognize him.”

Please check ayah 12:62 for complete tafsir.