All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
It is completely forbidden to help others in Riba (interest and/or usury) transactions as the Prophet said: “Allah has cursed the one who consumes Riba, the one who gives it to others, the one who records it and the one who witnesses it (its transaction).” He said: “All of them are equal in sin.” [Muslim]
As for insurance, it is a form of gambling. Allah, The Exalted, prohibits gambling in the Quran and called it al-Maysir (i.e. gamble and the linguistic origin of the word al-Maysir indicates that which comes easily).
Allah Says (what means): {O you who have believed, indeed, intoxicants, gambling, [sacrificing on] stone alters [to other than Allah], and divining arrows are but defilement from the work of Satan, so avoid it that you may be successful.} [Quran 5: 90]
The Scholars of Islam define insurance as follows: It is every contract that a person concludes as a winner or loser.
One exception of the above-stated concerning insurance is the cooperative insurance which is practiced in some Muslims countries.
Thus, since insurance is a form of gambling which Allah, The Exalted, has prohibited in the Quran and joined it with wine, it is forbidden to help in the transactions of insurance due to being a form of cooperation in sin and aggression.
Allah Says (what means): {And cooperate in righteousness and piety, but do not cooperate in sin and aggression. And fear Allah; indeed, Allah is severe in penalty.} [Quran 5: 2]
Therefore, it is forbidden to remain in this company if its activities are restricted to Riba and Maysir, and you have to look for another job.
Allah Says (what means): {And whoever fears Allah - He will make for him a way out. And will provide for him from where he does not expect. And whoever relies upon Allah - then He is sufficient for him.} [Quran 65: 2-3]
But, if this company runs many activities, some of which are forbidden and others are lawful, then you are allowed to run pure lawful activities only.
Allah knows best.