You seek forgiveness for them or not seek forgiveness for them; even if you seek forgiveness for them seventy times, never will Lord Allah forgive them, that is because they disbelieved with Allah and His Messenger, and Allah doesn’t guide a transgressing people.
When this verse was revealed, Messenger told: “If Allah forgives the hypocrites by seeking forgiveness for more than seventy times, I would do it”. Then as a result of this, verse 63: 6 was revealed which says: “It is the same whether you seek forgiveness for the hypocrites or not seek forgiveness for them, never will Allah forgive them; indeed, Allah doesn’t guide the transgressing people”.
Messenger and believers are commanded to neglect the hypocrites and to tell them words that penetrate their inner hearts as explained in verses 4: 63-64. Hypocrites have been killed since they are knowingly hiding Adhikr only with which the belief with Allah, Angels, Sprites, Prophets, Messengers, etc. can be formed as explained in verse 2: 146, 285. So, the believer or Messenger can’t seek forgiveness for them. It is told in verse 10: 33 that thus the word of your Lord is proved true in regards to the transgressors that indeed, they will not believe. The Messenger and believer can only seek forgiveness for the believing men and women as told in verses 47: 19 and 71: 28. The disbelieving and wrongdoing hypocritical leaders and their blind followers will argue, curse and blame each other in Hell as explained in verses 2: 166-167. See explanation 2: 6-7; 7: 175-176 and 9: 23-24.