Is working on developing routing devices to connect lottery equipment, a task for which a telecommunications contracting company was commissioned, and then I was asked to undertake other responsibilities unrelated to lotteries, permissible in Islamic law, and what should I do with the remaining and spent money if my income is not permissible?

Working on developing routers used in lotteries is forbidden because it is assisting in sin. If it is possible to avoid this work, then there is no harm in remaining with the company. However, if it is not possible, then one must leave the job. Money earned from this work, while ignorant of its prohibition or acting upon a fatwa that permits it, is permissible to benefit from, based on the Almighty's saying: ﴿So whoever receives an admonition from his Lord and desists, he may have what has passed.﴾ As for money earned after knowing of its prohibition, what has been spent of it incurs nothing but repentance. What remains, the forbidden portion of it must be disposed of by giving it to the poor. If a person is in need of the money, it is permissible for him to benefit from it according to his need, and to give the rest in charity.