How do we reconcile the Hadith about the door of repentance remaining open with verses indicating that Allah closed the door of repentance on Abu Lahab and the hypocrites, and can this happen in our time?

There is no contradiction between opening the door of repentance and Allah informing that specific individuals will not repent, as these individuals are exceptions to the general texts. Ibn Taymiyyah mentioned that if a servant wills obedience with a firm resolve, they are capable of it, and this is agreed upon among Muslims, though some extremist جبرية (Jabarites) dispute this, and their argument using the story of Abu Lahab is invalid. The fact that some people are prevented from repenting in our era is a reality, but no one can definitively assert that a specific individual has been prevented from repenting. The questioner is advised to study books on divine decree (Qadar) according to the methodology of Ahl al-Sunnah wa al-Jama'ah.

And Allah knows best.