All perfect praise be to Allaah, the Lord of the worlds. I testify that there is none worthy of worship except Allaah and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
Allaah has forbidden Riba (interest) and highlighted the punishment on the Day of Resurrection for those who consume and engage in such transactions. Allaah Almighty says (what means): {Those who consume Riba cannot stand [on the Day of Resurrection] except as one stands who is being beaten by Satan into insanity. That is because they say, "Trade is [just] like Riba." But Allaah has permitted trade and has forbidden Riba.} [Quran 2: 275]
Jabir narrated that the Prophet, sallallaahu ‘alayhi wa sallam, said, "Allaah has cursed the one who consumes Riba, the one who pays it, the one who writes its deed down, and those who witness it. All of them are equal in sin." [Muslim ]
Having consumed Riba for that long period, you are required, O my respectful brother, to sincerely repent to Allaah, regret your past deeds, and determine not to do that again in the future. For your repentance to be perfect, you have to hasten to pay back the sum as much as you can. You have to end this transaction and avoid the forbidden additional interests that result from your delay in paying back.
You should know that you are liable to pay back the value of these credits only, not the additional Riba-based interests. If the owners of these credit cards demand you to pay the interests, then you are blameless for doing so. If you are unable to do so, then you are also blameless for not hastening to pay it back, for Allaah does not charge a soul except (with that within) its capacity.
The issue of Hajj has nothing to do with this. Hajj is obligatory on you when you pay back the debts and still have enough money to perform it. Otherwise, it is not obligatory upon you, since ability is a prerequisite for Hajj being obligatory. Allaah Almighty says (what means): {And [due] to Allaah from the people is a pilgrimage to the House – for whoever is able to find thereto a way.} [Quran 3: 97]
Allaah Knows best.