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 is His slave and Messenger.
Your previous work that included selling wine in the duty-free shop was not lawful, as Allaah says (what means): {And cooperate in righteousness and piety, but do not cooperate in sin and aggression. And fear Allaah; indeed, Allaah is severe in penalty.} [Quran 5:2]
Also, Ibn ‘Umar narrated that the Prophet said, “Allaah has cursed wine, its drinker, its server, its seller, its buyer, its presser, the one who demands it to be pressed, its carrier, and the one to whom it is carried.” [Abu Daawood and others]
Moreover, Anas narrated that the Prophet said, “Allaah has cursed ten people in wine: its presser, the one who demands it to be pressed, its drinker, its carrier, the one to whom it is carried, its server, its seller, the one who consumes its price, its purchaser, and the one for whom it is purchased.” [At-Tirmithi]
Therefore, you must repent to Allaah and seek His forgiveness for having sold wine for that period of time.
As for your question about the pension that you earn because of your previous work in the duty-free shop, then if that pension is deducted from your salary while you were working, then you have to look at the deducted amount during the period of your work in selling wine, and this amount is unlawful and you have to get rid of it by paying it to the poor and the needy; whereas the amount that corresponds to the duration of your work in what is permissible is lawful for you to benefit from. Ibn al-Qayyim says, “If a person’s money is mixed with one unlawful dirham or more, then he should get rid of the amount that is unlawful and what remains is lawful for him.”
If the way that you earn the retirement pension is different, then please clarify it to us so that we may give an appropriate ruling on it.
Allaah knows best.