What should I do with my money in insurance companies after realizing its impermissibility? Should I pay the last installment to receive the full amount with interest after one year, or should I cancel the subscription and get my money back with a deduction?

It appears that the questioner must hasten to cancel the subscription, because prohibited contracts are forbidden, and the prohibition necessitates immediate and permanent cessation. An exception to the obligation of hastening is if there is significant harm to the questioner, in which case she may remain in the contract with the intention of recovering the principal and disposing of the excess by spending it on charitable causes.