Wa `alaykum as-Salamu wa Rahmatullahi wa Barakatuh.

If your father used the hotel facility against the stated rules of the company, then he is guilty of the breach of trust. If you were not aware of it, you are not accountable for the actions of your dad. He will have to account for it.

Islam is not merely performing rituals of prayer, fasting, etc. it also teaches us to fulfill the rights of God’s servants. Allah may forgive sins involving Him, and He will not forgive the sins involving the rights of His servants.

As for these, they must be forgiven by humans. Otherwise, one will have to pay for them on the day of judgment. Payment then is made through one’s good deeds; if they are still not paid off, then their sins will be imposed on the person, and he or she will be thrown to the fire of hell.

So, if you made use of the facility while knowing that your father was committing a breach of trust, then you ought to expiate for the same through istighfaar and charities. For details, you may also refer to a similar question answered in this session below.

Almighty Allah knows best.